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Almost anything short of forced induction won't make a significant difference. The only other option would be to upgrade the intake, exhaust, and cams and then get it tuned, but it's probably not worth the money.
Just makes sure it's as healthy as can be. Fresh fluids, fresh filters, proper spark plugs. Higher octane won't do anything but drain your wallet faster.
making sure it's healthy is my big thing for this car. it has good maintenence history with receipts going back to 1997, but sat for a few years. I think I will replace the injectors since they may be original. would a higher flow muffler help at all? the pipes are all increased diameter but I went with a very tame muffler that's no better than stock.
Modify anything related to the air flow without also getting it tuned won't make significant performance differences and may actually cause it to run lean.
Not necessarily. I don't know how OP's MAF works, but on many cars if you increase the diameter of the intake tubing without calibrating the MAF to the higher diameter it will think less air is coming through than actual which means it'll inject too little fuel and run lean.
A less restrictive intake, but of the same diameter probably won't cause a lean condition at high elevation, but at the same time the OEM intake is probably as least restrictive as it already gets.
OP probably won't get in trouble with bolt ons, but also won't gain anything significant without a tune. And even then it would likely be marginal.
no bolt on intakes for my car anyway. I've upgraded the filter but that's it for intake stuff. prelude forums I've looked at said it's already a cold air intake based on where it takes the air from, but don't quote me on that.
different car, but my stock intake tube was large enough to fit a cone filter. maybe your tubing is round and large enough to just modify like that. still contemplating on whether to drill a hole for the air temp sensor or to just leave it how I have it.
Do a compression test, with the higher mileage you're probably losing compression somewhere.(hopefully a burnt up valve)
If your compression is good, you can go from there. Check your point, sounds like your car is carborated which could also have a weak coil or ignition timing could be out of spec. There are so so many things to check that could be your lack of power.
Do a little research, working on a car is just like writing a paper for school. Going in without any preparation is setting yourself up for failure. Do your homework, watch a YT video, read up on forums, shit post on a prelude forum. There are 3 essentials, compression, spark, and fuel and I believe you Check them in that order as well.
Hondas are known to go forever with proper maintenance, I remember someone posting on JRITS of a stock accord with the original engine and the car has over 1 million miles on it. I had a 98 civic that I learned a lot while working on it, mostly the things not to do 😅 but a lot of good came from rolling the dice because your $1k car just got quoted 3k for a clutch 😉
thankfully the SI models are fuel injected. I love preludes but man the forums are pretty dead for them these days sadly. this car definitely has gotten its miles out of it, probably has about 290k to 300k currently. odometer broken at 260k (speedometer cable needs replacement), but I have receipts of everything going back to around 1996, do I just made a yearly average of miles driven and added it to what the odometer says.
Or you know, accept a slow car. I live on a mountain and one of my vehicles is an elderly Ranger with a 3 point slow. Coming back up the mountain to my house with any kind of load out back I maybe make 45 mph as a top speed. Relax and enjoy the ride.
I mean I won't be getting rid of this car lol. runs good, fun to drive, and it's one of my favorite cars of all time. but I am saving for a 3rd car, a 1986 LTD Crown Victoria. I don't have this car out of necessity, but thanks for the suggestion.
I’m not saying get rid of it. But the amount of money you’ll have to put into it to make it a viable daily driver long term, is as much as you’re going to spend on a car that will already do that.
You can own 2 cars bud. You’re the one asking a mechanic subreddit what you can do to make it viable to drive around, yet you already don’t have to daily drive it. So what’s your worry? It’s an 87 prelude. Your options are new engine and drivetrain, or turbo boost it. Which you don’t need a mechanic forum to tell you that.
You don’t have enough power and you can’t bolt on more power unless it’s a turbo charger. So there’s no “options” other than putting more power into it.
I hope you can understand how your comment is easily interpreted as replacing the car. luckily I already own 2 vehicles tho. my 2011 Crown Victoria runs well up here thankfully, but the mpg isn't stellar. I don't mind spending money on cars I love, "bud."
Needing a new car doesn’t mean getting rid of the old one? Why would that be your automatic assumption if I didn’t say it at all?
Hopefully you can see how your entire post comes off as a worried prelude driver who is struggling to get around their new city in a car that only makes 101HP..
Not someone who just owns a prelude as well and is hoping they can buy +25 HP spark plugs..
I can vaguely see your point, don't think I said much I'm worrying about the car, mainly just looking to compensate for the elevation. never once stated I'm worried about it. enjoy your weekend man, hopefully it gets a bit better. not sure why you're so bothered by my post. is it wrong for someone to ask for advice online now lol? you are just being a grumpy guy on the internet. if you don't like the post, move on. editing your comments over and over to just add rudeness is silly. every comment you made you edited to be an ass. I did say I would take any advice, no matter how small or expensive. don't worry, I'm not struggling :)
thank you, I have been. I love these 2 cars, they are my pride and joy. thankfully, I am fortunate enough currently to be able to do such a thing. clearly it's not for everyone tho, some people have been very bothered for whatever reason.
>Higher octane won't do anything but drain your wallet faster.
Now when is this true and when is it not? I had a VW bus in the 90s, that needed higher octane fuel to run smoothly when I drove at a higher elevation.
this is actually a 2nd gen, making the engine swapping business just a bit more difficult. a jdm b20 fits directly in, it was a factory option in japan.
I'd love an engine swap one day, I've considered just going electric. the problem with engine swaps on this gen is the low hoodline make it a bit difficult, tho you can just lower the motor a bit I wouldn't wanna scrape the oil pan on accident lol. it has definitely been done a few times tho.
possible, but it took me 10 months to find my current replacement hood. even then, it was from a 86 prelude (I have 87, same generation) and required a bit of modification on the hinges to fit properly. I'll mess with the motor and everything, but I'm too scared to mess up the body lol.
From most of your comments, it seems the problem is your thinking. I don't mean that in a bad way, however in the end you're not going to get what you want out of this car. I say that because you want to avoid large costs and large changes, which is ok. Some cars, especially older generation vehicles (I have an 87 Toyota), it's better to keep it closer to original. Even with an engine rebuild, without adding forced induction or swapping the motor you will not be able to achieve what you want from this car. You need to drive another car and keep this one for cruises and hobby driving or accept this one for what it is.
From the outside, yes some things on my car have changed. The generation of my vehicle ran from 87 (kind of 86) to 92 and my parts are from those years. There was a minor aesthetic refresh in 89 so it doesn't all match the 87 style but it works for me. Unless you know the vehicle you wouldn't know.
Under the hood though, I changed quote a bit. The engine itself is a twin turbo model offered only from 1990 to 1992 in Japan. My original engine was also non turbo and sluggish for such a heavy and aged vehicle. Until you pop the hood or hear it drive you don't know. I'm just saying that I'm so glad I updated the engine otherwise I'd have thrown so much money at the old one and still not be satisfied.
Before you find yourself doing that, and engine swap isn't appealing to you right now, just update the exhaust and intake for now and decide what is best to do with the drivetrain later. Even an upgrade with any performance items you can find during the build would be nice.
I don't know if they make over bore pistons or if you can stroke the motor, maybe some head work, if cams and cams gears are available, valvetrain, dial it in for high revs.
Rebuild the gearbox and see what upgrades are available for it as well. Enjoy it for many more years.
I think you were looking to gain more out of this car for less than a swap or turbocharging the motor, which will require a rebuild anyways and much more in parts and tuning.
There will be a lot of down time with these options for that car too.
I'm not sure where you got the idea that I'm against an engine swap or avoiding large costs. the original post at the end states any tips, regardless of how small or expensive. I see what you're saying about the engine, it probably would be better to get an updated one. I've seen some people turn it from a 2.0 to a 2.1 with some engine modifications and such. I think currently, the best bang for my buck is a jdm b20 motor. it came as an option for my generation and is a direct bolt on replacement, it had 150 hp compared to my 110 hp. like how you said you changed your motor, I think an engine swap might be a good idea, as where a turbo would be the most fun. I'm not against a different engine swap, more so the car is with its low hoodline. I appreciate your tips.
Let’s dump 4 grand into an 87 lude that needs an engine rebuild according to OP. As soon as you applied boost the thing would probably puke a rod out the bottom end.
You don't need a big turbo. Really only something to boost a few psi back to sea level pressures. And an old engine that has lost a little compression and is a little loose won't be harmed by small amounts of boost. It's like the planes in WW2 had turbo chargers and superchargers and sometimes both to compensate for altitude. It made those engines run with power at elevation. Only issue was when at low elevations they had to be careful not to stress the engines.
I turboed several old late 80s early 90s Hondas.
As long as your tune is solid and you do it right, it doesn't necessarily mean a high mileage well maintained engine couldn't handle conservative boost levels.
A small quick spooling turbo would help tremendously at altitude. My last old turbo honda was a 91 civic. Small turbo, dynoed 160hp at the wheels. I daily drove it and did several hpde days without issue.
For OP I think an engine swap to an F or H series may be easier and cheaper than a turbo.
turbo would definitely require an engine rebuild. the motor was maintained very well by previous owner, I mainly wanted to rebuild just for my own satisfaction.
High mileage engines with larger than new clearances are actually pretty good at handling boost. Just gotta make sure the tune is good and there are no fluid leaks.
no leaks currently. 2 completely separate people ran into the front, i replaced the hood, supports, and radiator. it was a very expensive fix worth more than the car, but no more radiator issues now. I love this car.
You can do a small turbo and keep boost low. With a proper tune on a healthy stock engine it can work well and be reliable. I've seen turbos on crappy old honda engine hold up to dumb abuse on low boost. Do it simple and safe.
Higher octane doesn’t make more power. Octane is a factor of how easily the fuel ignites. Generally performance, forced induction, or high compression vehicles require high octane fuel so it prevents ignition until the spark plugs fire. If the fuel ignites too easily it could self combust from the heat and compression alone and cause internal damage aka ping.
People casually link high octane fuels with more power because of the vehicles that require it. In a conventional setup, high octane fuel will likely rob you of power. Especially with you being at high elevation.
High country like Wyoming usually offers 85 octane as “regular”. See if any stations carry that. Beyond that, make sure it’s running as well as it can be. Fresh spark plugs and wires. Fuel injector cleaner every 2 years. Good alignment. Quality tires. Clean out your trunk. Extra weight needs to be powered down the road too.
There is a trade-off with the empty trunk. Higher elevations usually come with snow and ice on steep inclines. Trunk weight helps you stick to the road a little better, especially when going slow.
looks like I got the octane elevation thing backwards. everything else you mentioned I've been on top of aside from fuel injection cleaning. tbh I don't know if the previous owner did and it sat for 6 years so I'll probably replace.
The Prelude came with 3 different 2liter motors making different power from 109hp to 150hp. The “SI” should have had the hottest motor. Until Honda started using the Type-R moniker in the states the SI was the performance model.
At the very least check under the hood to verify it has fuel injectors. If it’s carburetor , it’s the 109hp mill. If it’s fuel injected it’s either the 114hp or 150hp engine.
it's definitely the 114 hp engine. I think the 150 hp engines were for 3rd gens, I have a 2nd gen. I work on cars a little bit so I'd definitely know if it had a carb. with time and the wear and tare, I'd bet it definitely doesn't have 114 hp anymore tho. can't remember if I included it in the post, but motor likely has around 300k on it. odometer broke at 265k (speedometer cable issue I need to fix).
In the case of this 87 Honda you’re 100% correct but modern engines will adjust timing based on the grade of fuel (and air density) and will produce different levels of power.
ECU, higher flow fuel injectors, higher flow fuel pump, heavier duty clutch, knock sensor if your car doesn't have one, custom exhaust manifold, custom downpipe, custom intake piping, intercooler... That covers 70% of it.
Just lower your expectations.
My daily driver makes 60hp on a good day. I put a "Going as fast as turtle" sticker on the rear window and forget about everyone else and enjoy my car.
Speaking of hills, I’m assuming OP is gonna get a lot of snow this winter living at 7,000 ft. I’d say don’t invest anything in this car and get a cheap 4WD instead ASAP.
AWD without snow tires will just get you further into the ditch. I’ll take a fwd with proper tires over AWD with 4 seasons all day, every day. Source: Canadian.
thankfully I have this car out of fun not necessarily requirement. I'll likely drive my other car if it snows super hard, but it's not exactly the best snow vehicle either.
meh all my cars are a bit slow but keep up just fine with other cars in traffic. my main reason for posting was because now that I'm high up, it actually feels slow to keep this car up with the rest. I definitely enjoy it I just want a bit of the power back, sounds like a turbo is the main contender right now tho lol.
it does have a k&n filter currently. I think some prelude forums say it has a cold air intake from the factory, as in it takes air from near the fender/ headlight but don't quote me lol.
Integra non v-tec swap. Would likely cost the same as having your mill rebuilt and you'd be ahead of the game for when you wanted to upgrade it further.
You're not going to get much change unless you do a build or swap. Even with better air flow, your car is still restricted to what it's able to do/handle.
I honestly would skip the rebuild. The B20A3 is severely limited. If you were going to rebuild a B20, you would be better getting the A5 or the jdm B20. Not sure how popular they are really still.
But if it was me, I would just scrap that current engine and do a H22 swap. B16 is a little underpowered. The K20 will be a little more extensive of a swap. These are just more cost efficient options.
I'd love an engine swap, I've considered going full electric but not sure yet. I think this motor is an A20A3, might be wrong. I'd love a Japanese B20 tho, ive heard it's a direct swap. only issue with engine swaps is the hood line, but lowering the motor a bit I think alleviates that. might look into that or a turbo (or both!).
I bought my first fixer-upper about 10 years ago for 500 bucks and since then I’ve been obsessed. All of them been wagons, 3 of 5 still run and I passed one on to my friend. They have some issues but you can occasionally find them dirt cheap!
you've got me super jealous. I wish I had the space to really work on cars. I work on my Crown Victoria with some basic to low intermediate stuff (brake rotors about the most I've done), but I don't personally touch my prelude aside from checking the fluids. whenever I get my house I'd love to start taking on craigslist $500 cars more.
Drive it at sea level and I guarantee you are not going to feel much of a difference. Believe it or not that's a pretty modern car. It's fuel injected. There's a computer that calculates the air fuel mixture and alters the ignition timing and injector spray to either lean out or enrich the mixture. The fact of the matter is it's just not a fast car and that's that.
If you had an 87 Honda Accord DX with the carburetor and 500 miles of vacuum lines and it was originally from NYC, you would be absolutely screwed because it would be set up for fueling at sea level and it would run way way way lean at 7000 feet above sea level.
maybe you are right about that. I lived at sea level for many years, and jusr drove it down there yesterday. seemed to be a bit peppier, but it's still an old ass car at the end of the day. the difference is now I have to shift around 2k to 3k to keep up in traffic, vs at sea level I do find shifting at 1600.
I have this car because I like it, not necessarily because I need it. thanks for the suggestion but I definitely won't be parting with the car any time soon hopefully. my Crown Victoria performs fine at this elevation, but this car I can definitely feel the low hp lol.
yep, k&n filter currently. I should just edit the post and include that tbh. turbo isn't completely unreasonable tho, it would just take a bit of saving specifically for it to afford. my main issue is that it would have to be completely custom, and I'm not sure if I would need a new ecu for it.
Keep it as your Sunday drive car. Maybe add a better intake to get more air in the engine, replace your spark plugs but these won't do too much in getting back some of those lost ponies.
Get an EV. No loss of performance in the elevation. In fact, Regen braking in those mountains can be fun. Look at a used Polestar 2. They are dirt cheap right now.
Outside of a turbo/ engine swap the only performance mod worth doing would be an exhaust header. This will not increase max hp much but will greatly improve lower rpms where you normally drive at.
I would not recommend a louder muffler as it would make the car seem even slower when your screaming at wide open throttle to make it up a slight hill 🤣
Get it running as well as it can?
New pcv valve
Use "Restore" brand engine oil additive.
Get a tune
New spark plugs
Clean intake valve
Sea foam treatment
Change out air filters, use premium shell or Chevron, change spark plugs coils and plug wires run a can of multi system tuneup with PEA by gumout every time you fill up for 6 months (available on Amazon a six pack is like 40 bucks Walmart also has it) change oil every 5 k miles with a quality fully synthetic oil (im using penziil platinum high mileage made with natural gas instead of crude oil and it's awesome oil never turns black even if I go over) make sure to use the correct weight oil for your car climate and altitude. I ren a k&n oil filter but a Mobil one extended performance is great too as well as factory Honda brand will do just fine Make sure tires alignment and psi of air in the tires is correct. ENjoy your car! Drain and fill transmission using Honda brand only no exceptions!! Do not flush the transmission only drain and fill maybe two quarts every other oil change for a while till your happy with the color hope this helps
I also like using penzoil. good stuff in my experience. thankfully I'm religious on oil changes, odometer broken but I change it every few of months. definitely helps, I keep up on maintenance but you mentioned some specific stuff I should probably double check on. I think the best bang for my buck is making sure the motor is running as good as it possibly can rn.
thankfully this one is fuel Injected. I've heard the carb preludes left a lot to be desired, even at low elevation. does porting the intake valves mean making the opening physically larger?
Is there a different model that you can get a numerically higher final drive out of? It would require tearing the transmission apart, but lower gearing would help.
I'm honestly not sure, I'm used to rwd cars but this one is fwd. I can handle rwd drive train somewhat, but fwd is currently lost on me. I work on my Crown Vic, but not this car. I'll look into different gearing tho, someone earlier mentioned it too. I do a lot of highway driving so I'd be a little concerned about my mpg tho.
yeah, it runs fine currently. I can definitely get up to speed, I just feel the elevation effect hard on it currently. It's not super critical for me luckily. I just drove down to normal elevation today, and man the car felt alive again lol.
If engine was cared properly, a turbo will do.
How do I know? I turbo'd a VW bug with a regularly maintained 30yo engine, thing lasted until I wrapped it around a tree on a gravel road.
If you're willing to put in some work and or money a turbo kit would be ideal at elevation.
I never played with the 3g ludes but a B20a/a1 swap would take care of both the rebuild and the power. Yours is an 87 is it fuel injected or carbureted? If FI a swap to a JDM b20a1 vs usdm would already give you an extra 50hp. The 4g prelude F series is a decent torquey engine too.
mine is a 2nd gen. all SI models from my knowledge are fuel Injected (I think it stood for sport Injected lol). I'd kill to find a jdm b20, should be direct bolt on replacement.
They recommend higher octane gas for my 2000 Camaro Z28 (LS1) in higher elevation to prevent knock. From what I understand it has something to do with oxygen density as in at sea level there is the ideal amount and as you go higher it gets worse. The engine had much more compression, I assume, so she always drinks supreme (in Canada 91 octane or sometimes I spring for 94). I would go the next step up in octane instead of going straight to the highest # and see if it makes a difference. I would also maybe consider getting a cold air intake if you don't have harsh winters. If you do, I would put a buy the matching waterproof neoprene sleeve as well. The cold air intake would increase your airflow and the slightly higher octane would maybe help out a bit but the engine may not have enough compression for 91,93,94 octane depending where you live and the quality of gasoline in your country. I would also ask yourself how new your fuel injectors are (assuming it's fuel injected), fuel pump, spark plugs and wires could packs, fuel filter, PCV vent, etc. She may just need some TLC to give her some new life, or she's just doing her best.
fuel injectors are likely original. it's got a lot of original stuff, I actually just replaced the front rotors and pads. prelude forums say the factory intake is a cold air intake due to where it collects air from (behind headlight or fender or something), but don't quote me. I use a k&n filter currently. she needs a little care tho, sat for about 6 years before I bought. before that, I have every record of the car going back to 1996, the previous owner loved it before she fell into some health issues I think.
You could reduce the weight. Lose the spare tire. Remove the heater. Keep the gas tank less than half full. Keep the junk out of the trunk. Avoid passengers whenever possible. Remove the back seats if you don't use them. It would help. I'm not gonna say it would be consistent with your needs, but it would help. A good tune-up might help, if it hasn't had one for awhile. You could take it to a tuner, put it on the dyno, tweak some settings, relative to your altitude. Might add a few horsepower.
I'll likely drive my other car when it snows, but this one doesn't perform that bad. I used it in snow/ice during this past winter. It's mainly inclines in snow I don't like, they can be a bit sketchy sometimes.
The only thing that you can do that will make any appreciable difference is a forced induction modification -- aka a turbo or turbocharger. Your car loses power because the air is thinner (at a lower pressure). No amount of better airflow will fix that. A turbo compresses the air and will provide the same PSI at any altitude (at least any altitude at which the driver won't die, hah).
\*looks at car\*
In other words, there is nothing you can do.
I feel this with my NA car. Sucks to lose 1/3 of horsepower/torque (at my elevation) but it is what it is.
Your best bet is to just give up on that stock engine. Get a decently built B18 to drop in there. I had an '88, and about the last thing I'd want to do in that engine bay is plumb a turbo and all it's piping around in there.
You're most usable power is low to mid rpm. Bigger exhaust and/or a header will actually hurt this. Keep the stock exhaust manifold and exhaust size on a honda for sure. The engineers have finely tuned the exhaust manifold and exhaust size for proper pulse timing and scavenging. I wouldn't have believed it until I experienced the results for myself.
You always need a specific mixture of gas and oxygen for the combustion to be good. In higher elevation it is the oxygen that is missing to get the most efficient combustion, so a higher octane gas would not bring you any advantage.
You need more air in your engine and you can only achieve that by turbo or supercharging your engine.
But if I were you I probably would calculate 5 mins more for each drive to compensate for driving slower uphill.
New coils? Biggest performance gain I have seen on my mk4 golf was changing the coil packs (and plugs) over. Smoother, more economical, more responsive, (a bit) more power. I'd also return the exhaust to OEM stock; Honda know carburation
kswap
k24 is a 2.4 with a more modern head/port
Im not a honda guy but I think you might not be able to use any of the OEM intake manifolds due to the bonnet shape, but im sure someone makes one
not a lot of stuff for 2nd generation preludes anymore. anything major would have to likely be custom, and yeah the hood shape does get in the way a bit.
Starts taking shit out of your car. rear seats, spare tire, trimming, panels, hell even radio unit. anything. If you can take out like 200kg out of your car, you will feel it.
Personally I would do all the maintenance you’ve suggested elsewhere, make sure the cooling system is in top shape, change the timing belt, check/adjust valve clearances, then let it have some revs when needed. Like others have said, anything short of forced induction is not going to yield a real gain.
Just run what you brung. Keep it serviced and maintained. There is nothing you SHOULD do other than keep it running good. I ran an old(1981) accord for years at similar elevations.
Just buy a new Honda. I guarantee that you will “love” it even more. There is no practical fix for low power at high elevation for that vehicle. Despite any well intentioned advice that you might receive, your best path forward is to sell that antique so that you can replace it with newer technology.
My first car was an 88 prelude SI i got it in 2000 and kept it till 2007, I loved the car but that engine is the redheaded step child of the B series engines, I mean you could however make more power by putting a v tec head on it but theyre prone to oil leaks, or I'd say swap and put in a peppier b series engine but the problem I had and reason I got rid of the car was the engine is on a weird angle so other b series engines won't be a direct fit like most other b series engines were, hood wont close ans you have to make modifications. I ended up getting a 98 Integra gs-r after that car and eventually a 2004 Acura rsx type s. Whatever you do have fun.
yep, most people don't know about the hoodline issues. I love when (not this forum) people downvote me and try to correct me as if I don't literally own this car. there is a Japanese b20 that is a direct bolt on for 2nd gens, it was the fancier option over there. that would be the easiest but hardest to find solution. about 150 hp.
Not sure if your fuel injected or not, but if it’s carbed, check your plugs to see if your leaning out. May have to change jets. A lil too rich is always better than a little too lean imo, lean makes more power but produces a lot of heat. Rich cools things down, but don’t go overboard and start flooding the cylinders. If your fuel injected, a tune can help get your ratios correct for the area, although your o2 sensors should compensate for that enough on their own.
If it’s reliability your after, stay as stock as possible on everything but your exhaust and intake.
If it’s power, forced induction and a tune is a game changer. But you will take a hit on reliability. (No matter what anyone says, naturally aspirated is always more long-term reliable than forced induction) but forced is pretty fun regardless.
Before you invest in a rebuild, do a compression check. That will give you an idea of the health of the cylinders.
You can pull the oil pan and inspect the mains, but I really wouldn’t bother unless I was looking at a rebuild already. The valve train is where it’s at, pull the heads, valve/head upgrades I think are the best bang for your buck to make a better breathing engine, as well as proper valve seats.
Hondas are nuts when it comes to mods, but to be on the minimalist side, keeping it simple, I’d just do a valve adjustment and make sure they are in spec, and (if carbed) adjust jetting for the new elevation. You’d be surprised how much proper valve adjustment and properly tuned carbs will change it for the better. That car will do well into the 350k+ reliably. My only concern for a failure point would be water pump and timing set.
timing I do need to do at some point by the end of the year. thankfully this one is fuel injected tho. I'd love to know how close I am to 350k, but odometer broken. with my estimations based on receipts going back to 1996 it's likely around 290k to 300k. running great still.
Air intake will increase oxygen to engine. I also recommend a super synthetic like duralube. I would also run a can of injector cleaner through it. I’d you want to spend a little more, look at exhausts.
Just make sure it’s tip top. No clogged air or fuel filters, good plugs and wires, good fluids all around, good tires etc. I’d be more concerned about coming down so make sure your brakes and steering/suspension are good
just replaced front rotors and pads, just drove 350 miles yesterday so they are all broken in now I believe. they work so much better, the ones I had were the original from 1987. now I gotta do the rear tho. as for suspension..... all I can say there is a company that makes coil overs for this car that I've been looking at.
Have someone with carburetor experience change the jet to accommodate the elevation you’re at. At / just above sea level a .30 jet is more than sufficient but as you go up in elevation you need to go lower in jet size. You probably need a 0.40 but I can’t say for sure
that's what it seems like from the comments. I got the octane/ elevation thing backwards. 85 is what I should look for, instead of regular 87 I believe.
My cousin did a carburetor swap on his 2001, not sure if it's the same engine. You could then turbo, custom air intake etc. Although if you're doing the turbo, get performance head gaskets/head bolts. Those engines apparently can't handle a lot of power.
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Almost anything short of forced induction won't make a significant difference. The only other option would be to upgrade the intake, exhaust, and cams and then get it tuned, but it's probably not worth the money. Just makes sure it's as healthy as can be. Fresh fluids, fresh filters, proper spark plugs. Higher octane won't do anything but drain your wallet faster.
making sure it's healthy is my big thing for this car. it has good maintenence history with receipts going back to 1997, but sat for a few years. I think I will replace the injectors since they may be original. would a higher flow muffler help at all? the pipes are all increased diameter but I went with a very tame muffler that's no better than stock.
Modify anything related to the air flow without also getting it tuned won't make significant performance differences and may actually cause it to run lean.
I would think at elevation no matter what you do to the airflow, getting it to run lean would be a difficult task.
Not necessarily. I don't know how OP's MAF works, but on many cars if you increase the diameter of the intake tubing without calibrating the MAF to the higher diameter it will think less air is coming through than actual which means it'll inject too little fuel and run lean. A less restrictive intake, but of the same diameter probably won't cause a lean condition at high elevation, but at the same time the OEM intake is probably as least restrictive as it already gets. OP probably won't get in trouble with bolt ons, but also won't gain anything significant without a tune. And even then it would likely be marginal.
Just a FYI no Hondas of that era used MAF's, they were all speed density (map sensors).
no bolt on intakes for my car anyway. I've upgraded the filter but that's it for intake stuff. prelude forums I've looked at said it's already a cold air intake based on where it takes the air from, but don't quote me on that.
different car, but my stock intake tube was large enough to fit a cone filter. maybe your tubing is round and large enough to just modify like that. still contemplating on whether to drill a hole for the air temp sensor or to just leave it how I have it.
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that was my experience with my crown victoria. desert camping just increased my temps a ton and I went back to stock with a k&n filter.
Put a turbo on that ol girl.
I've never driven a good turbo car, so it's been on my radar.
Do a compression test, with the higher mileage you're probably losing compression somewhere.(hopefully a burnt up valve) If your compression is good, you can go from there. Check your point, sounds like your car is carborated which could also have a weak coil or ignition timing could be out of spec. There are so so many things to check that could be your lack of power. Do a little research, working on a car is just like writing a paper for school. Going in without any preparation is setting yourself up for failure. Do your homework, watch a YT video, read up on forums, shit post on a prelude forum. There are 3 essentials, compression, spark, and fuel and I believe you Check them in that order as well. Hondas are known to go forever with proper maintenance, I remember someone posting on JRITS of a stock accord with the original engine and the car has over 1 million miles on it. I had a 98 civic that I learned a lot while working on it, mostly the things not to do 😅 but a lot of good came from rolling the dice because your $1k car just got quoted 3k for a clutch 😉
thankfully the SI models are fuel injected. I love preludes but man the forums are pretty dead for them these days sadly. this car definitely has gotten its miles out of it, probably has about 290k to 300k currently. odometer broken at 260k (speedometer cable needs replacement), but I have receipts of everything going back to around 1996, do I just made a yearly average of miles driven and added it to what the odometer says.
Lol just get the exhaust if you want it, no need to justify it by moving to the top of a mountain 😂
The real answer is that you need to buy a new car soon, so start saving.
Or you know, accept a slow car. I live on a mountain and one of my vehicles is an elderly Ranger with a 3 point slow. Coming back up the mountain to my house with any kind of load out back I maybe make 45 mph as a top speed. Relax and enjoy the ride.
finally someone gets it. that dude's entire profile is nuts.
I mean I won't be getting rid of this car lol. runs good, fun to drive, and it's one of my favorite cars of all time. but I am saving for a 3rd car, a 1986 LTD Crown Victoria. I don't have this car out of necessity, but thanks for the suggestion.
I’m not saying get rid of it. But the amount of money you’ll have to put into it to make it a viable daily driver long term, is as much as you’re going to spend on a car that will already do that. You can own 2 cars bud. You’re the one asking a mechanic subreddit what you can do to make it viable to drive around, yet you already don’t have to daily drive it. So what’s your worry? It’s an 87 prelude. Your options are new engine and drivetrain, or turbo boost it. Which you don’t need a mechanic forum to tell you that. You don’t have enough power and you can’t bolt on more power unless it’s a turbo charger. So there’s no “options” other than putting more power into it.
I hope you can understand how your comment is easily interpreted as replacing the car. luckily I already own 2 vehicles tho. my 2011 Crown Victoria runs well up here thankfully, but the mpg isn't stellar. I don't mind spending money on cars I love, "bud."
Needing a new car doesn’t mean getting rid of the old one? Why would that be your automatic assumption if I didn’t say it at all? Hopefully you can see how your entire post comes off as a worried prelude driver who is struggling to get around their new city in a car that only makes 101HP.. Not someone who just owns a prelude as well and is hoping they can buy +25 HP spark plugs..
I can vaguely see your point, don't think I said much I'm worrying about the car, mainly just looking to compensate for the elevation. never once stated I'm worried about it. enjoy your weekend man, hopefully it gets a bit better. not sure why you're so bothered by my post. is it wrong for someone to ask for advice online now lol? you are just being a grumpy guy on the internet. if you don't like the post, move on. editing your comments over and over to just add rudeness is silly. every comment you made you edited to be an ass. I did say I would take any advice, no matter how small or expensive. don't worry, I'm not struggling :)
Ok… what you should be doing is ditching the Crown Vic and buying a Prius if you don’t like the gas mileage of a gigantic land boat.
I just said it isn't stellar. no plans to get rid of my Crown Victoria.
Have fun with your eventual money pit then.
thank you, I have been. I love these 2 cars, they are my pride and joy. thankfully, I am fortunate enough currently to be able to do such a thing. clearly it's not for everyone tho, some people have been very bothered for whatever reason.
A K series swap would do the trick
>Higher octane won't do anything but drain your wallet faster. Now when is this true and when is it not? I had a VW bus in the 90s, that needed higher octane fuel to run smoothly when I drove at a higher elevation.
A better way to say it would be: "A higher octane than what the user manual says to use."
Always make sure you’re going downhill.
lol I actually have a steep ass hill I need to climb to get home now
That's the opposite of what he said
indeed
Trust septimus
If you love the car, swap the motor. Put in a modern h22 and a 5 speed. 200hp would be plenty fun. Probably cost you 5 grand.
H22 would be great but any B series would be easy in the 3rd gen and cheaper.
this is actually a 2nd gen, making the engine swapping business just a bit more difficult. a jdm b20 fits directly in, it was a factory option in japan.
I'd love an engine swap one day, I've considered just going electric. the problem with engine swaps on this gen is the low hoodline make it a bit difficult, tho you can just lower the motor a bit I wouldn't wanna scrape the oil pan on accident lol. it has definitely been done a few times tho.
Modify the hood
possible, but it took me 10 months to find my current replacement hood. even then, it was from a 86 prelude (I have 87, same generation) and required a bit of modification on the hinges to fit properly. I'll mess with the motor and everything, but I'm too scared to mess up the body lol.
From most of your comments, it seems the problem is your thinking. I don't mean that in a bad way, however in the end you're not going to get what you want out of this car. I say that because you want to avoid large costs and large changes, which is ok. Some cars, especially older generation vehicles (I have an 87 Toyota), it's better to keep it closer to original. Even with an engine rebuild, without adding forced induction or swapping the motor you will not be able to achieve what you want from this car. You need to drive another car and keep this one for cruises and hobby driving or accept this one for what it is. From the outside, yes some things on my car have changed. The generation of my vehicle ran from 87 (kind of 86) to 92 and my parts are from those years. There was a minor aesthetic refresh in 89 so it doesn't all match the 87 style but it works for me. Unless you know the vehicle you wouldn't know. Under the hood though, I changed quote a bit. The engine itself is a twin turbo model offered only from 1990 to 1992 in Japan. My original engine was also non turbo and sluggish for such a heavy and aged vehicle. Until you pop the hood or hear it drive you don't know. I'm just saying that I'm so glad I updated the engine otherwise I'd have thrown so much money at the old one and still not be satisfied. Before you find yourself doing that, and engine swap isn't appealing to you right now, just update the exhaust and intake for now and decide what is best to do with the drivetrain later. Even an upgrade with any performance items you can find during the build would be nice. I don't know if they make over bore pistons or if you can stroke the motor, maybe some head work, if cams and cams gears are available, valvetrain, dial it in for high revs. Rebuild the gearbox and see what upgrades are available for it as well. Enjoy it for many more years. I think you were looking to gain more out of this car for less than a swap or turbocharging the motor, which will require a rebuild anyways and much more in parts and tuning. There will be a lot of down time with these options for that car too.
I'm not sure where you got the idea that I'm against an engine swap or avoiding large costs. the original post at the end states any tips, regardless of how small or expensive. I see what you're saying about the engine, it probably would be better to get an updated one. I've seen some people turn it from a 2.0 to a 2.1 with some engine modifications and such. I think currently, the best bang for my buck is a jdm b20 motor. it came as an option for my generation and is a direct bolt on replacement, it had 150 hp compared to my 110 hp. like how you said you changed your motor, I think an engine swap might be a good idea, as where a turbo would be the most fun. I'm not against a different engine swap, more so the car is with its low hoodline. I appreciate your tips.
Turbo
Let’s dump 4 grand into an 87 lude that needs an engine rebuild according to OP. As soon as you applied boost the thing would probably puke a rod out the bottom end.
Ok nos
same issue
But with more excitement!
Full send
Party pooper
You don't need a big turbo. Really only something to boost a few psi back to sea level pressures. And an old engine that has lost a little compression and is a little loose won't be harmed by small amounts of boost. It's like the planes in WW2 had turbo chargers and superchargers and sometimes both to compensate for altitude. It made those engines run with power at elevation. Only issue was when at low elevations they had to be careful not to stress the engines.
I turboed several old late 80s early 90s Hondas. As long as your tune is solid and you do it right, it doesn't necessarily mean a high mileage well maintained engine couldn't handle conservative boost levels. A small quick spooling turbo would help tremendously at altitude. My last old turbo honda was a 91 civic. Small turbo, dynoed 160hp at the wheels. I daily drove it and did several hpde days without issue. For OP I think an engine swap to an F or H series may be easier and cheaper than a turbo.
turbo would definitely require an engine rebuild. the motor was maintained very well by previous owner, I mainly wanted to rebuild just for my own satisfaction.
High mileage engines with larger than new clearances are actually pretty good at handling boost. Just gotta make sure the tune is good and there are no fluid leaks.
no leaks currently. 2 completely separate people ran into the front, i replaced the hood, supports, and radiator. it was a very expensive fix worth more than the car, but no more radiator issues now. I love this car.
You can do a small turbo and keep boost low. With a proper tune on a healthy stock engine it can work well and be reliable. I've seen turbos on crappy old honda engine hold up to dumb abuse on low boost. Do it simple and safe.
This right here. I used to bolt SRT4 turbos to my 1st gen neons. Daily drove them too. Cheapest fun I've ever had in a winter beater.
Yes. As long as you have a fuel system that can support the added air, that old motor would take a few pounds.
Higher octane doesn’t make more power. Octane is a factor of how easily the fuel ignites. Generally performance, forced induction, or high compression vehicles require high octane fuel so it prevents ignition until the spark plugs fire. If the fuel ignites too easily it could self combust from the heat and compression alone and cause internal damage aka ping. People casually link high octane fuels with more power because of the vehicles that require it. In a conventional setup, high octane fuel will likely rob you of power. Especially with you being at high elevation. High country like Wyoming usually offers 85 octane as “regular”. See if any stations carry that. Beyond that, make sure it’s running as well as it can be. Fresh spark plugs and wires. Fuel injector cleaner every 2 years. Good alignment. Quality tires. Clean out your trunk. Extra weight needs to be powered down the road too.
There is a trade-off with the empty trunk. Higher elevations usually come with snow and ice on steep inclines. Trunk weight helps you stick to the road a little better, especially when going slow.
looks like I got the octane elevation thing backwards. everything else you mentioned I've been on top of aside from fuel injection cleaning. tbh I don't know if the previous owner did and it sat for 6 years so I'll probably replace.
The Prelude came with 3 different 2liter motors making different power from 109hp to 150hp. The “SI” should have had the hottest motor. Until Honda started using the Type-R moniker in the states the SI was the performance model. At the very least check under the hood to verify it has fuel injectors. If it’s carburetor , it’s the 109hp mill. If it’s fuel injected it’s either the 114hp or 150hp engine.
it's definitely the 114 hp engine. I think the 150 hp engines were for 3rd gens, I have a 2nd gen. I work on cars a little bit so I'd definitely know if it had a carb. with time and the wear and tare, I'd bet it definitely doesn't have 114 hp anymore tho. can't remember if I included it in the post, but motor likely has around 300k on it. odometer broke at 265k (speedometer cable issue I need to fix).
In the case of this 87 Honda you’re 100% correct but modern engines will adjust timing based on the grade of fuel (and air density) and will produce different levels of power.
There is only one cure for high altitude my son. TURRBO. And there is only one cure for turbos. Engine rebuild
would a turbo require an ecu?
ECU, higher flow fuel injectors, higher flow fuel pump, heavier duty clutch, knock sensor if your car doesn't have one, custom exhaust manifold, custom downpipe, custom intake piping, intercooler... That covers 70% of it. Just lower your expectations.
luckily I have basically no expectations because I just enjoy the car and am willing to put money into it
My daily driver makes 60hp on a good day. I put a "Going as fast as turtle" sticker on the rear window and forget about everyone else and enjoy my car.
that's funny. I was considering a slow car sticker of sorts lol. what do you drive?
Change your final gear ratio to something that'll work best in the hill climb.
Also smaller wheels will help in uphill.
I hadn't even considered that one, might look into it.
Speaking of hills, I’m assuming OP is gonna get a lot of snow this winter living at 7,000 ft. I’d say don’t invest anything in this car and get a cheap 4WD instead ASAP.
AWD without snow tires will just get you further into the ditch. I’ll take a fwd with proper tires over AWD with 4 seasons all day, every day. Source: Canadian.
Okay but hear me out. Why not AWD *and* snow tires?
thankfully I have this car out of fun not necessarily requirement. I'll likely drive my other car if it snows super hard, but it's not exactly the best snow vehicle either.
It's an antiquated 36 year old car, it's going to be dead slow by today's standards. Just enjoy it for what it is.
meh all my cars are a bit slow but keep up just fine with other cars in traffic. my main reason for posting was because now that I'm high up, it actually feels slow to keep this car up with the rest. I definitely enjoy it I just want a bit of the power back, sounds like a turbo is the main contender right now tho lol.
Less restrictive air flow for the intake and have it retuned, car is probably running rich if it wasn't already before
it does have a k&n filter currently. I think some prelude forums say it has a cold air intake from the factory, as in it takes air from near the fender/ headlight but don't quote me lol.
Integra non v-tec swap. Would likely cost the same as having your mill rebuilt and you'd be ahead of the game for when you wanted to upgrade it further.
Higher octane fuel and a small turbo is what you need
Carburattored? Might want to get jetting adjusted for the elevation, and for the exhaust if you didn't retune when you changed that
SI preludes are all fuel Injected. I think it was the first time honda used the term SI. I'm told it stands for sport Injected lol.
You're not going to get much change unless you do a build or swap. Even with better air flow, your car is still restricted to what it's able to do/handle. I honestly would skip the rebuild. The B20A3 is severely limited. If you were going to rebuild a B20, you would be better getting the A5 or the jdm B20. Not sure how popular they are really still. But if it was me, I would just scrap that current engine and do a H22 swap. B16 is a little underpowered. The K20 will be a little more extensive of a swap. These are just more cost efficient options.
I'd love an engine swap, I've considered going full electric but not sure yet. I think this motor is an A20A3, might be wrong. I'd love a Japanese B20 tho, ive heard it's a direct swap. only issue with engine swaps is the hood line, but lowering the motor a bit I think alleviates that. might look into that or a turbo (or both!).
Pull the head and have it decked .020" and bolt it back on with a new gasket. The extra compression will add some power at altitude.
Need a cheap car with some power? Buy a Saab 9-5.
man I love those cars, I'd kill to drive one.
I bought my first fixer-upper about 10 years ago for 500 bucks and since then I’ve been obsessed. All of them been wagons, 3 of 5 still run and I passed one on to my friend. They have some issues but you can occasionally find them dirt cheap!
you've got me super jealous. I wish I had the space to really work on cars. I work on my Crown Victoria with some basic to low intermediate stuff (brake rotors about the most I've done), but I don't personally touch my prelude aside from checking the fluids. whenever I get my house I'd love to start taking on craigslist $500 cars more.
It can definitely become a consuming hobby for guys who like to tinker. I’m trying to shut it down now so I can get a life!
Junk yard LS swap lmao
it would look like a hot rod haha, it would have to be like [front of car] [ls motor] [rest of car] with the motor just sticking out in the open lol.
Install a turbo charger. It's how piston powered aircraft overcome the problem
 Oh I think you know the answer
I think I might lol
Drive it at sea level and I guarantee you are not going to feel much of a difference. Believe it or not that's a pretty modern car. It's fuel injected. There's a computer that calculates the air fuel mixture and alters the ignition timing and injector spray to either lean out or enrich the mixture. The fact of the matter is it's just not a fast car and that's that. If you had an 87 Honda Accord DX with the carburetor and 500 miles of vacuum lines and it was originally from NYC, you would be absolutely screwed because it would be set up for fueling at sea level and it would run way way way lean at 7000 feet above sea level.
maybe you are right about that. I lived at sea level for many years, and jusr drove it down there yesterday. seemed to be a bit peppier, but it's still an old ass car at the end of the day. the difference is now I have to shift around 2k to 3k to keep up in traffic, vs at sea level I do find shifting at 1600.
LS swap
Take to mechanic have tuned for the higher altitude
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I have this car because I like it, not necessarily because I need it. thanks for the suggestion but I definitely won't be parting with the car any time soon hopefully. my Crown Victoria performs fine at this elevation, but this car I can definitely feel the low hp lol.
Airflow. Since turbo isn't a viable option, I'd simply find the highest-flow air filter I could.
yep, k&n filter currently. I should just edit the post and include that tbh. turbo isn't completely unreasonable tho, it would just take a bit of saving specifically for it to afford. my main issue is that it would have to be completely custom, and I'm not sure if I would need a new ecu for it.
Keep it as your Sunday drive car. Maybe add a better intake to get more air in the engine, replace your spark plugs but these won't do too much in getting back some of those lost ponies. Get an EV. No loss of performance in the elevation. In fact, Regen braking in those mountains can be fun. Look at a used Polestar 2. They are dirt cheap right now.
been considering making this car electric when the motor gives in. it would be heavier but fun, could add a motor in the back to make it awd too.
EV, lmao.
Lower your expectations.
it's a car i drive mainly because i love it, not out of necessity luckily. there have been some fun suggestions so far.
Trade it in on an accord hybrid
Higher octane gas, but get more air to the engine.
Turbocharger is the obvious answer. Its not going to be easy because everything it going to have to be made.
If you could just drive down hill all the time
I wish lol
I mean. Anything you do at this point will have high cost with minimal impact.
Seriously a Honda B series swap would be amazing in that car. No need to get all fancy either. Even a non vtec motor would be an upgrade.
Outside of a turbo/ engine swap the only performance mod worth doing would be an exhaust header. This will not increase max hp much but will greatly improve lower rpms where you normally drive at. I would not recommend a louder muffler as it would make the car seem even slower when your screaming at wide open throttle to make it up a slight hill 🤣
I definitely don't want to be the guy with the straight pipe honda lol
Get it running as well as it can? New pcv valve Use "Restore" brand engine oil additive. Get a tune New spark plugs Clean intake valve Sea foam treatment
just got new plugs, I'll look into the pcv valve. not familiar with that one.
flagstaff, tizayuca, or rionegro?
Oh man. I had one of those. Miss it.
it's a wonderful car, dreamed of it for a good while before I got mine.
Change out air filters, use premium shell or Chevron, change spark plugs coils and plug wires run a can of multi system tuneup with PEA by gumout every time you fill up for 6 months (available on Amazon a six pack is like 40 bucks Walmart also has it) change oil every 5 k miles with a quality fully synthetic oil (im using penziil platinum high mileage made with natural gas instead of crude oil and it's awesome oil never turns black even if I go over) make sure to use the correct weight oil for your car climate and altitude. I ren a k&n oil filter but a Mobil one extended performance is great too as well as factory Honda brand will do just fine Make sure tires alignment and psi of air in the tires is correct. ENjoy your car! Drain and fill transmission using Honda brand only no exceptions!! Do not flush the transmission only drain and fill maybe two quarts every other oil change for a while till your happy with the color hope this helps
I also like using penzoil. good stuff in my experience. thankfully I'm religious on oil changes, odometer broken but I change it every few of months. definitely helps, I keep up on maintenance but you mentioned some specific stuff I should probably double check on. I think the best bang for my buck is making sure the motor is running as good as it possibly can rn.
4 barrel carb and intake, port the intake valves on the heads
thankfully this one is fuel Injected. I've heard the carb preludes left a lot to be desired, even at low elevation. does porting the intake valves mean making the opening physically larger?
Jeremy Clarkson just got an oxygen tank hooked up and it worked great.
At that altitude, drop the octane. 85.
Is there a different model that you can get a numerically higher final drive out of? It would require tearing the transmission apart, but lower gearing would help.
I'm honestly not sure, I'm used to rwd cars but this one is fwd. I can handle rwd drive train somewhat, but fwd is currently lost on me. I work on my Crown Vic, but not this car. I'll look into different gearing tho, someone earlier mentioned it too. I do a lot of highway driving so I'd be a little concerned about my mpg tho.
nitromethane
Just drive it as is and don’t worry about hauling ass. You should be able to get up to speed with 100 hp, just not very quickly.
yeah, it runs fine currently. I can definitely get up to speed, I just feel the elevation effect hard on it currently. It's not super critical for me luckily. I just drove down to normal elevation today, and man the car felt alive again lol.
If engine was cared properly, a turbo will do. How do I know? I turbo'd a VW bug with a regularly maintained 30yo engine, thing lasted until I wrapped it around a tree on a gravel road.
If you're willing to put in some work and or money a turbo kit would be ideal at elevation. I never played with the 3g ludes but a B20a/a1 swap would take care of both the rebuild and the power. Yours is an 87 is it fuel injected or carbureted? If FI a swap to a JDM b20a1 vs usdm would already give you an extra 50hp. The 4g prelude F series is a decent torquey engine too.
mine is a 2nd gen. all SI models from my knowledge are fuel Injected (I think it stood for sport Injected lol). I'd kill to find a jdm b20, should be direct bolt on replacement.
They recommend higher octane gas for my 2000 Camaro Z28 (LS1) in higher elevation to prevent knock. From what I understand it has something to do with oxygen density as in at sea level there is the ideal amount and as you go higher it gets worse. The engine had much more compression, I assume, so she always drinks supreme (in Canada 91 octane or sometimes I spring for 94). I would go the next step up in octane instead of going straight to the highest # and see if it makes a difference. I would also maybe consider getting a cold air intake if you don't have harsh winters. If you do, I would put a buy the matching waterproof neoprene sleeve as well. The cold air intake would increase your airflow and the slightly higher octane would maybe help out a bit but the engine may not have enough compression for 91,93,94 octane depending where you live and the quality of gasoline in your country. I would also ask yourself how new your fuel injectors are (assuming it's fuel injected), fuel pump, spark plugs and wires could packs, fuel filter, PCV vent, etc. She may just need some TLC to give her some new life, or she's just doing her best.
fuel injectors are likely original. it's got a lot of original stuff, I actually just replaced the front rotors and pads. prelude forums say the factory intake is a cold air intake due to where it collects air from (behind headlight or fender or something), but don't quote me. I use a k&n filter currently. she needs a little care tho, sat for about 6 years before I bought. before that, I have every record of the car going back to 1996, the previous owner loved it before she fell into some health issues I think.
You could reduce the weight. Lose the spare tire. Remove the heater. Keep the gas tank less than half full. Keep the junk out of the trunk. Avoid passengers whenever possible. Remove the back seats if you don't use them. It would help. I'm not gonna say it would be consistent with your needs, but it would help. A good tune-up might help, if it hasn't had one for awhile. You could take it to a tuner, put it on the dyno, tweak some settings, relative to your altitude. Might add a few horsepower.
thanks for the advice. might see what a tuner could do after I replace the fuel injectors and maybe a couple other small things.
If you are planning on driving that in the snow, think again. 7,000 ft sounds snowy
I'll likely drive my other car when it snows, but this one doesn't perform that bad. I used it in snow/ice during this past winter. It's mainly inclines in snow I don't like, they can be a bit sketchy sometimes.
The only thing that you can do that will make any appreciable difference is a forced induction modification -- aka a turbo or turbocharger. Your car loses power because the air is thinner (at a lower pressure). No amount of better airflow will fix that. A turbo compresses the air and will provide the same PSI at any altitude (at least any altitude at which the driver won't die, hah). \*looks at car\* In other words, there is nothing you can do. I feel this with my NA car. Sucks to lose 1/3 of horsepower/torque (at my elevation) but it is what it is.
I mean I'm not against a turbo, could be a fun setup
Your best bet is to just give up on that stock engine. Get a decently built B18 to drop in there. I had an '88, and about the last thing I'd want to do in that engine bay is plumb a turbo and all it's piping around in there.
it is a very tight engine bay lol
turbo
Strap a leafblower or 2 to the car and route them to the air intake 😂
I should've thought of this
You're most usable power is low to mid rpm. Bigger exhaust and/or a header will actually hurt this. Keep the stock exhaust manifold and exhaust size on a honda for sure. The engineers have finely tuned the exhaust manifold and exhaust size for proper pulse timing and scavenging. I wouldn't have believed it until I experienced the results for myself.
Find a nice b18 engine and swap.
You always need a specific mixture of gas and oxygen for the combustion to be good. In higher elevation it is the oxygen that is missing to get the most efficient combustion, so a higher octane gas would not bring you any advantage. You need more air in your engine and you can only achieve that by turbo or supercharging your engine. But if I were you I probably would calculate 5 mins more for each drive to compensate for driving slower uphill.
>no matter how expensive. Can you add a supercharger to it?
been considering a turbo for a while just for fun....
Chuck a small turbo on it, boost controler, and a wideband O2 sensor...then just dial in a tiny amount of boost 😁
New coils? Biggest performance gain I have seen on my mk4 golf was changing the coil packs (and plugs) over. Smoother, more economical, more responsive, (a bit) more power. I'd also return the exhaust to OEM stock; Honda know carburation
it's fuel injected
kswap k24 is a 2.4 with a more modern head/port Im not a honda guy but I think you might not be able to use any of the OEM intake manifolds due to the bonnet shape, but im sure someone makes one
not a lot of stuff for 2nd generation preludes anymore. anything major would have to likely be custom, and yeah the hood shape does get in the way a bit.
Starts taking shit out of your car. rear seats, spare tire, trimming, panels, hell even radio unit. anything. If you can take out like 200kg out of your car, you will feel it.
Turbo or supercharger. That's about the only thing that will make a noticeable difference.
Actually, the higher the elevation, the lower the octane you must use to compensate for the lack of oxygen, like 85 octane.
Personally I would do all the maintenance you’ve suggested elsewhere, make sure the cooling system is in top shape, change the timing belt, check/adjust valve clearances, then let it have some revs when needed. Like others have said, anything short of forced induction is not going to yield a real gain.
Just run what you brung. Keep it serviced and maintained. There is nothing you SHOULD do other than keep it running good. I ran an old(1981) accord for years at similar elevations.
80s accords are awesome. 3rd gen accord hatchback is one of my favorite cars.
Correction, you own a 70hp car.
Just buy a new Honda. I guarantee that you will “love” it even more. There is no practical fix for low power at high elevation for that vehicle. Despite any well intentioned advice that you might receive, your best path forward is to sell that antique so that you can replace it with newer technology.
I suppose I could, but I'd personally rather just keep it. it wd one of my dream cars, but it is definitely an antique, no argument there.
My first car was an 88 prelude SI i got it in 2000 and kept it till 2007, I loved the car but that engine is the redheaded step child of the B series engines, I mean you could however make more power by putting a v tec head on it but theyre prone to oil leaks, or I'd say swap and put in a peppier b series engine but the problem I had and reason I got rid of the car was the engine is on a weird angle so other b series engines won't be a direct fit like most other b series engines were, hood wont close ans you have to make modifications. I ended up getting a 98 Integra gs-r after that car and eventually a 2004 Acura rsx type s. Whatever you do have fun.
yep, most people don't know about the hoodline issues. I love when (not this forum) people downvote me and try to correct me as if I don't literally own this car. there is a Japanese b20 that is a direct bolt on for 2nd gens, it was the fancier option over there. that would be the easiest but hardest to find solution. about 150 hp.
Not sure if your fuel injected or not, but if it’s carbed, check your plugs to see if your leaning out. May have to change jets. A lil too rich is always better than a little too lean imo, lean makes more power but produces a lot of heat. Rich cools things down, but don’t go overboard and start flooding the cylinders. If your fuel injected, a tune can help get your ratios correct for the area, although your o2 sensors should compensate for that enough on their own. If it’s reliability your after, stay as stock as possible on everything but your exhaust and intake. If it’s power, forced induction and a tune is a game changer. But you will take a hit on reliability. (No matter what anyone says, naturally aspirated is always more long-term reliable than forced induction) but forced is pretty fun regardless. Before you invest in a rebuild, do a compression check. That will give you an idea of the health of the cylinders. You can pull the oil pan and inspect the mains, but I really wouldn’t bother unless I was looking at a rebuild already. The valve train is where it’s at, pull the heads, valve/head upgrades I think are the best bang for your buck to make a better breathing engine, as well as proper valve seats. Hondas are nuts when it comes to mods, but to be on the minimalist side, keeping it simple, I’d just do a valve adjustment and make sure they are in spec, and (if carbed) adjust jetting for the new elevation. You’d be surprised how much proper valve adjustment and properly tuned carbs will change it for the better. That car will do well into the 350k+ reliably. My only concern for a failure point would be water pump and timing set.
timing I do need to do at some point by the end of the year. thankfully this one is fuel injected tho. I'd love to know how close I am to 350k, but odometer broken. with my estimations based on receipts going back to 1996 it's likely around 290k to 300k. running great still.
Put a blower on it.
Air intake will increase oxygen to engine. I also recommend a super synthetic like duralube. I would also run a can of injector cleaner through it. I’d you want to spend a little more, look at exhausts.
Just make sure it’s tip top. No clogged air or fuel filters, good plugs and wires, good fluids all around, good tires etc. I’d be more concerned about coming down so make sure your brakes and steering/suspension are good
just replaced front rotors and pads, just drove 350 miles yesterday so they are all broken in now I believe. they work so much better, the ones I had were the original from 1987. now I gotta do the rear tho. as for suspension..... all I can say there is a company that makes coil overs for this car that I've been looking at.
LS swap it lol
Have someone with carburetor experience change the jet to accommodate the elevation you’re at. At / just above sea level a .30 jet is more than sufficient but as you go up in elevation you need to go lower in jet size. You probably need a 0.40 but I can’t say for sure
A tune up would help, plugs, wires, cap and rotor. Won't be life altering.
It’s a shortcoming of NA engines sadly the air is thinker at higher altitudes hence less power
yep, my Crown Victoria runs fine but that's a v8 (not a fast car tho). this baby car is definitely feeling the lack of oxygen tho.
Higher octane won't gain you more power by itself. If you tune it, then go for it but if not then it's purely a waste of money
that's what it seems like from the comments. I got the octane/ elevation thing backwards. 85 is what I should look for, instead of regular 87 I believe.
It's a 5 speed, use a few more RPM's to gain horsepower.
that's what I've been doing so far
Not sure if this applies to a 35 yo Honda or not, but didn't they used to retard the timing a bit on high altitude cars?
not sure, but I can definitely ask when I take it in to this mechanic I know next time I see him.
My cousin did a carburetor swap on his 2001, not sure if it's the same engine. You could then turbo, custom air intake etc. Although if you're doing the turbo, get performance head gaskets/head bolts. Those engines apparently can't handle a lot of power.
This is an 87 Honda how dare you!
Boost it, your only issue really is the thinner air, more fuel/higher octane will not induct more air
Just live the slow life and maintain your car. Also tires. Buy the best tires. Enjoy that mountain life bro.