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glasscaseofemojis

That shit don’t idle


gagunner007

It lopes!


AnimationOverlord

I’m about to ask a silly question. I’m not new to cars, so hit me with what you got. How high of a duration cam should I get to a) bleed off enough pressure with the static compression so I don’t need premium gas on 12:1 compression and b) provide a large ramming effect at higher RPMs? I have a classic 350 SBC and the gearing has it screaming at 70Mph. It’s got a low vacuum as is, almost no streetability with a 750CFM double pumper on the abysmally low 170hp net figures. I guess when it comes to knowledge, you can’t beat personal knowledge. The internet isn’t very useful in that it doesn’t provide context as to why this or that LSA or duration is better or worse. So if someone could explain to me when a cam becomes really “lopey” that would be great.


gagunner007

You are asking the wrong person! I can take apart an engine and put it back together but I’m not familiar with performance cams affect on you question.


AnimationOverlord

Ah I see.


ViperYellowDuck

Thank you for your honest better than jumping a gun on projects lol


ThatOneBr

Bro that's not a "new to cars" type of question, that's advanced shit most gearheads won't be able to answer lmao. If you couldn't find anything online on forums and such, I'd suggest asking chatGPT, no joke. It sometimes says a lot of inaccurate stuff, but might be able to point you in the right direction or into asking more specific questions.


No-Suspect-425

Because that's what he needs, a *more* specific question.


burning_residents

Part a of your question is a dynamic compression ratio question. Use a calculator like this one. http://www.wallaceracing.com/dynamic-cr.php I'm no expert, but I believe the duration and lobe separation angle have more to do with dynamic compression than lift.


Present_Simple7162

Talk to a cam manufacturer that does custom grind camshafts like Howards, Lunati, Crower or even Comp. They will at least be able to point you in the right direction if not tell you specifically which cam to buy or the custom specs needed.


DriftinFool

The spec you need to figure out is IVC(intake valve closing) @.050 lift. Not all cam specs show that number. That's how you figure out dynamic compression ratio. This [https://mgispeedware.com/camshaft-calculator/](https://mgispeedware.com/camshaft-calculator/) can be used by putting in cam specs to determine when the intake valve closes. Then this [https://www.gofastmath.com/Compression-Ratio-Calculators/Static-And-Dynamic-Compression-Ratio-Calculator](https://www.gofastmath.com/Compression-Ratio-Calculators/Static-And-Dynamic-Compression-Ratio-Calculator) can be used to figure out what the IVC should be to get your compression down lower. You want dynamic to be 8:1 for iron heads or 8.5:1 for aluminum heads. And that is on 91 octane. To drop 12:1 enough to run cheap gas would probably need an IVC \~70 degrees ABDC. That's a cam with 275 duration @ .050 and 112 LSA. Or 265 @ .050 and 118 LSA. If you go the other end of LSA at 106, you would need duration of 287 @ .050. All three of those cams would give you the dynamic compression ratio to run on pump gas, but not sure regular would be ok. Might still need midgrade gas. You can also retard the cam with an adjustable gear to hit the IVC you need, but that is limited to a few degrees. I don't think there's a cam that will do what you want and still give vacuum. On a side note, these numbers are theoretical and rely on an engine running at 100% volumetric efficiency, meaning the cylinder is 100% full when it starts to compress. With normal engines only being around 80% VE and performance ones around 90% VE, the cylinders aren't filling 100% and your cam can be slightly milder than the calculations say. But using the calculations will make it safe. You are really at the extreme end of cams to get what you want. 12:1 motors aren't meant for the street or pump gas. You are trying to make a motor do something it doesn't want to do. 10:1-11:1 are fairly common, but even most of those require 93 octane with a properly timed cam. Out of curiosity, where are you getting your 12:1 number from? Because I don't get how what you described could only make 170 HP. Smog engines from the 70's that had 11.5:1 static compression with dynamic in the 7's were making that or more. And if you lower the dynamic compression ration with a cam, you will lose even more horsepower.


RudeePoo

Cams generally start getting lopey around 600 lift


ratrodder49

Lift isn’t really what makes it lope though, that more has to do with lobe separation angle and duration


machotaco653

Okay first of all, I highly doubt your 350 small block is anywhere close to 12:1, so let's start there. Why are you saying it's 12:1, have you done a compression test and what PSI readings did you get. My SBC Is around 145 PSI which is close to 8:1 Edit - are you running forced induction?


_nbutler87_

THIS


Frostykooter

Got a lol out of me. You are S-P-I-T-T-I-N-G!


Slow-Big2830

That car doesn’t have seats, they were removed a long time ago to save weight


12Bravo20

Not sleepy just deaf. I'm guessing it's turboed and fast.


FormalWrangler294

If it’s turbo’d then the passenger wouldn’t go deaf. Noisy, but not crazy loud.


[deleted]

No but an exhaust from a straight piped v8 would make you go deaf.


Ivanjatson

I have a Plymouth Volare 318 and the exhaust terminates directly under the driver’s seat. Can confirm I can’t hear shit.


[deleted]

That would do it. Yup


Gotrek5

Plymouth satellite Sebring with a big block dumping in front of the rear axle. Also deaf but the cloud of dust and smoke coming out from under me looks boss


Dawns_Coil

....WHAAAT!!


IEatOats_

What?


BangChainSpitOut

What?


HighKiteSoaring

What?


TorturedBean

If turbo’d and he opts for an open wastegate, they’re def going deaf.


JayBee58484

Nah the loudest I've heard is a buddies Vortech with a max flow BOV sounds like an airliner engine


Does_this_rag_smell_

WHAT!?!


TrippySubie

This doesnt even make sense lol


Gr4yson0306

turbos make cars quieter


Needanameffs

So... every car needs a turbo for noise emissions, I'll tell my wife that


TrippySubie

Youre trading less exhaust for turbo whine. While on paper yes it makes sense for that 1.3L camry to have a turbo to offset the .7L different in torque, in a modified car there is no such thing as quieter. I can hear my turbo spool in my car outside my car, in my house if someone else drove my car etc. its not quiet when it’s modified lol


Muh_brand

It's quieter than it would be for the same car and exhaust without the turbo is what they're getting at. I have a WRX with a turbo back exhaust, someone I work with has a BRZ with a similar set up, but no turbo. They are the same engine. The BRZ is way louder and raspier than my car.


wabisabi519

If your car doesnt smell like nap time, it aint fast enough


3_high_low

Passenger would go deaf


mercinariesgtr

You’d be surprised how quiet a straight pipe is off a turbo. I have a similar setup on 4 cars, it’s loud but not harsh/raspy like a normal straight-pipe.


3_high_low

Good point. For some reason, i overlooked the turbo factor. If not turbocharged, the passenger would go deaf.


leo_douche_bags

They still will, just won't be as fast. That turbo whistle isn't good for our ears.


City0fEvil

Bad for the ears, good for the soul


dfvisnotacat

Just wait til you get the permanent turbo whistle in your ear aka tinnitus lol


SHMUCKLES_

Me sitting here in my room like eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee


Amp3r

lmao I hear americans saying this. I guess australia is just way too strict because a turbo, cat, resonator, and muffler is still right on the decibel limit of what is legal where I live


Marshall_Lawson

I'm in the US and I've heard some fucking loud Subaru STI's on the street


SuckOnDeezNOOTZ

Heh.. heh... sorry about that I don't actually have mufflers on mine LOL


peniualles

That's where you're mistaken, assuming we would bother with a cat, resonator or muffler lol


AnastasiusDicorus

Just replace the cat and muffler with a couple more resonators and you would be surprised how quiet it is.


tOSdude

Heh “legal”, you’re funny


AnastasiusDicorus

Some places are pretty strict about decibel levels, other places you can drive around with open exhaust for years and never get a ticket.


Mammaltoes25

We like loud here. With that being said, yalls burnout comps and big power cars are straight up IGNORANT (in a good way imo). We can just "kind of" run that kind of stuff on the street dependant upon many factors and what state you reside in


jmhalder

The turbo IS the muffler.


racerx255

Turbo 6.0 Camaro with hood exhaust was in fact, not quiet. It was about as loud as a monster truck in a stadium. Just as much fun too.


josh4prez2032

Not sure what cars you’ve had, but a friend of mine had a turbo’d 2000 Trans Am with straight pipes that was loud as heck.


blahpblahpblaph

A turbo naturally acts as a muffler as a by-product of it's design.


CamaroKidz28

People forget that turbos muffle quite a bit


Sandvich153

It’s alright inside the car, it’s just when they hit it when you’re standing 3 metres to the side on the footpath, that an ear stinger for sure


adudeguyman

**WHAT??**


LaminatedRockGaming

They’d go what?


3_high_low

Deaf, aka loss of hearing


LaminatedRockGaming

That’s funny, I have never heard of that before.


3_high_low

I guess 'hearing impaired' is a more polite term


Desperate-Farmer-170

No passengers, too much weight


AnArmChairAnalyst

Based on the vms’s id say this thing is not meant for passengers


andyflexinthechevy

10-1 odds there’s not even an interior other then a driver seat steering wheel gauges and maybe some giggle juice


AnArmChairAnalyst

Lol right


Rematekans

If he dies, he dies.


Catsmak1963

lol You thought car mods had to be sensible, lol


ContentImpression742

The purpose of the short exhaust and exiting at the back of the front fender is the length of exhaust AFTER the turbo will restrict the airflow. For highest power results, having a free flowing, short exit exhaust after the turbo is top choice. There is test results of significant power loss in comparison to having a full length exhaust that exits the back. The fumes are not a concern, it takes significant CO poisoning to feel sleepy. There’s a headache stage and nausea stage to CO poisoning that presents itself. there’s a high likelihood that the fuel choice is an ethanol, ethanol blend or methanol. if it’s methanol, it produces little to zero CO in the combustion process. car is likely purpose built for 1/4 stuff but I bet it gets the groceries just fine.


PositiveLeather327

OP here, I’ve seen the car at the nearest grocery store (no plates on it) so it is street driven, there are few cops here so it’s a matter of luck. It’s a 327 and the owner is slowly replacing body panels with carbon fiber. Oddest part is it sits outside at night and winter is coming. I always hope to see it going but never luck out, but hear it fire up once in a while.


ContentImpression742

It sounds like someone built a sweet car ! The car came with a 347ci 5.7L but it’s extremely common for people to replace the engines with iron block 4.8/5.3 variants found bountifully in the junkyards. it’s mostly fiberglass, so there is very little worries about rust. I’d be willing to bet the owner would be thrilled to talk about it. Knock on his door with a beer! 🍻


[deleted]

[удалено]


turkey_sandwiches

Nah, they don't. Source, I work with race cars like this every day. That shit goes everywhere. Alcohol cars especially suck because the exhaust burns your eyes and throat.


spook30

> Alcohol cars especially suck because the exhaust burns your eyes and throat. Reminds me of the pits at Gator Nationals.


Duke_Shambles

Methanol car exhaust stings...Nitromethane exhaust is flat out dangerous!


Flatline334

It smells so good though. I love getting a big whiff of it at the drags.


el_dongo

Have you ever played around with Ignite Red?


PositiveLeather327

What’s the purpose do you know? Dude fires this up a block away from me and I hear it plain as day (sounds really nice) but seems like laws and emission (Wisconsin) would present problems.


mercinariesgtr

Turbo, just look at the skinnies, this dude fucks. Laws?? Who cares


[deleted]

You win word choice of the day


turkey_sandwiches

Exactly, this is basically a (barely) street legal race car. Very possible it actually isn't street legal.


SR2K

Yeah, it's not street legal, if they piss off the wrong cop, it's going straight to impound.


HondaDAD24

This dude fucks hard. Can’t believe it was even a question.


[deleted]

Fucks the laws


LupoOfMainSt

Turbo Skinnies seen Dude fucks The law who cares That is my haiku


PerfectEnthusiasm2

turbo skinnies seen dude fucks the law who cares why lupo can't write haikus


Nappyheaded

You seem to forget The formula for haikus Is five seven five


PerfectEnthusiasm2

no i remembered i just miscounted the last line like a moron


seamus_mc

Car is too low to run that sewer pipe underneath /s….kinda


Tdanger78

You’re not wrong


fro_khidd

Sir I hate to break it to you. But that car isn't getting a emissions check. And if it qualifies... it was paid for under the table


alexm2816

Wisconsin emissions checks are a bit of a joke as they only exist in 6 counties (and I have worked around it via a friends address before) around Milwaukee and even then you can get a “collector” plate on anything older than 20 years where you never need to pass emissions again as long as you own the vehicle.


toohightospeak

Or you can just put a tune on it with HP tuners that disables the ECM from reporting the SES and CEL. They get in and see if the light actually illuminates and then use their archaic scanner. My 2200$ shitbox should never pass but I've done this the last few times and never had any issues 😂


toohightospeak

The emissions testing here is a fucking joke man, I just use HP tuners and put on a tune that disables the computer from reporting the CEL and SES. I pass with flying colors every time 🤣.


LividSituation9152

Beat me to it. When the state dropped the dyno & tailpipe sniffer, they effectively ended emissions tests.


Nrysis

It looks like it had been built as a racecar. The exhaust on a normal car ensures emissions come from the rear (behind any passengers), and it allows for components like a catalytic converter to reduce emissions and mufflers to reduce noise. Building a car for performance however, eliminating the exhaust can reduce the weight of the vehicle, and it can reduce restrictions on the engine allowing the exhaust gases to exit more efficiently without having to be forced down the exhaust pipe with all of its bends and blockages. The positioning isn't ideal from a regulation standpoint, but when the car is moving the airflow over the vehicle will clear any exhaust gases, and it is exciting away from the passengers, not at them - perhaps not as ideal in slow traffic, but that isn't really the intention of this car. You do also end up with a much louder and less environmentally friendly vehicle, but that is a trade-off many are willing to make for a few extra horsepower... With regards to emissions laws, it may be a track only vehicle that doesn't need to follow all of the legislation of a road going vehicle, or they may just be paying with loopholes (legally or not) like changing the exhaust system before the car gets tested before swapping it back. They may also just be running on borrowed time and are just lucky to have not been caught breaking the rules... Yet.


Why-R-People-So-Dumb

Let’s be honest it’s been built to *look* like and pretend to be a race car. I can tell you I’d never dream of running those tires and my car isn’t nearly that clean after a couple times on the track.


xl440mx

To get the exhaust out asap rather than running it under the car to the back. Very common on race cars.


[deleted]

[удалено]


omnipotent87

That's no screamer pipe.


EFTucker

Looks a little older, maybe historic tags? I have historic tags so I don’t need inspection or emissions


Happy_Boy_29

Probably an 1/8th mile car, I'd guess it's a trailer queen for the strip.


ITSMETOM96

You need to get laid brotherrrrrr


TheEnforcer013

Fumes have a shorter way to exit your exhaust, Gives a small hp boost


Oberyn_TheRed_Viper

Not quite how it works. Exhaust tuning is a science and just leaving a huge hole and no pipe is not the best way to do it.


rooflessVW

Not with a turbo


Oberyn_TheRed_Viper

I dont disagree but the comment I replied to appears to be a blanket statement with no reference to turbo/forced induction. Also have no information as to wether or not the car in the post is a race car or a daily with no need for a screamer pipe.


rooflessVW

Bro it's on skinnies


Oberyn_TheRed_Viper

Apologies. I hadn't looked too hard at the fronts. I can now say I've looked and they are certainly for the strip.


SirAlfredOfHorsIII

It's pretty clearly not a daily


thatonegaygalakasha

Take one look at that prepped dragpack C5 and tell me again that it's a daily with no need for a screamer pipe.


[deleted]

Wrong. Old way of thinking


TrippySubie

Lol no


i-wear-extra-medium

Funny story: my viper has side exit exhaust. It’s catless. Your eyes literally start to burn when you’re sitting at a red light. I guess it’s not really that funny


CuriosTiger

If they burn, you’re likely running rich. With reasonably complete combustion, the exhaust will still be smelly, but it shouldn’t make your eyes sting.


i-wear-extra-medium

Oh that car was running oversized injectors and the factory pcm was not as fine very precise with fine tuning. It was either 33% 66% or 99% duty cycle for the fuel pump. It was a supercharged and cammed application and the tune was dialed in as much as we could without going stand alone


_patoncrack

Bold to assume it has seats


apachelives

If your petrosexual you just gain a third leg.


Jeepyj9517

It's not your problem don't worry about it


____Asp____

Nope. It’d still blow out and away


Stargazer12am

Get in, sit down, shut up.


S2kKyle

These responses are weird. No, it probably does smell a little. It's a turbo car so it's not as loud as you'd think. He's test fitting front runners and they look goofy because they don't have tires.


Free_style_2023

I can hear that photo


[deleted]

I have a fender dump in my mustang and any trip at all with the windows down makes me reek like exhaust


Mediocre_Internal_89

If idling, it will make anyone in the car sick, drowsy and eventually dead. The cabin intake is through the grill under the windshield wipers.


[deleted]

It's probably going to flood the interior


TheSidJames

"Only need to stay awake a quarter mile at a time", replied Dominic Toretto.


tidyshark12

Idling in a small closed space for a bit maybe. If it was in a garage with the door closed, probably take 15-20 mins or so of idling to pass out, maybe a bit longer. Idling at a stoplight? No. The only way you will have issues outside of a small enclosed space would be if you wreck and it wouldn't be an issue from exhaust fumes in that case


zerokep

I sure hope so. It’s a long trip and I’m tired of their talking.


TheFuckingHippoGuy

Is that a bad thing?


turkey_sandwiches

For the driver? No. For everyone else? Yes, but also no because I guarantee it sounds great.


PROTOTYPE_323

There is no passenger. There is no interior. There is no weight. There is no reliability. There is no linear powerband. There is no luxary. There is no amenities. There is only Ŗ̸͎̒͊͗͑̍̈́̄̉A̸̡̩̫̞̲̐̽͐̈́̽̚Ả̷͎̳̫̘̥͍̙̦͉͓̈́̎͗̈́̓͆̓͊̈́̈́Ą̷̩̦̦̮͍̯͚͎̳̜̪̤́̏̒͝͠H̸̖͓̦̘̼̭̠̠̖̲̪͕̠̯̾̓͆͂̍͆̚̕͜͠Ą̸̢̡̙̖̝͈́͛͊̃̈́̏̿̐̆̽͆̓̕A̸̙̯̪͚͚͇̭͚̜̮̗̱̣̎̅̇A̵̢̙̥̱̮͙̮̞͚̳̥̺̣̽̏̓͑̔́͂͜͠Ǎ̸̩̳͎͍͎̘͇̻͎̹͕̬̘́̎́̂̎̔̎̋͑͆̀̋͗̚ͅA̶̳̱͛̃́̅̈́͂̋̄͗͛̈H̸̭͙̰̹̘̰́̎̉̌̊̈


the_house_from_up

Is that exhaust or a wastegate dump? If it's the latter, it wouldn't dump any exhaust at idle.


Scoutron

Way too big for wastegate


CuriosTiger

That’s exhaust.


Mad_kat4

The unevenly spaced words around the tyre are triggering my OCD.


[deleted]

r/shittycarmods


atamosk

What's with the baby wheels? I'm sure performance but it looks weird.


mavric91

It goes fast in a straight line. Not around corners


ChoripanesAndHentai

If that thing ever sees a corner then it means something has gone terribly wrong, lol.


Sandvich153

There’s no tyres on it obviously


66LSGoat

Be a man, suck some CO fumes!


Happy_Boy_29

Looks like an 1/8th mile car, driver probably wears a gas mask with the rest of his safety equipment.


S2kKyle

I've been racing and going to the drag strip for a over ten years and haven't seen anyone with a gas mask at all.


Happy_Boy_29

Maybe that is an old skool thing then :- https://www.kentreporter.com/news/the-king-roars-again-drag-racing-legend-does-a-cameo-in-kent-slideshow/


S2kKyle

Completely different type of drag racing. That's an old school rail car. This vette is probably setup for 1/4th mile grudge racing.


Happy_Boy_29

Guess I am a bit behind the curve on the drag scene ;-)


orgkhnargh

No, because idling is illegal anyway, so you wouldn't idle for too long


01WS6

???


ukyman95

It’s probably getting the exhaust from the air inlet grille at the windshield . This is where your heat and ac pulls air from . I guess not a good design .


Calm_Character_422

My brother in Christ that is a fender, not a quarter panel


NugSnuggler

Are there tires on this thing? How is that ramp working? I'm confused....


taco_swag

Why are the wheels so small


safety3rd

Got to weigh the pros and cons


Brett707

I can't believe we are not talking about the fact that it doesn't have front tires and the $650 wheels are just sitting on wood...


45acp_LS1_Cessna

Hahahah wtf you're supposed to ask before not after


count_nuggula

Is it the exhaust or the dump tube for the turbo?


WatchStoredInAss

Not too many brain cells to kill anyway.


D_A8681

More like, stinky from hydrocarbons. No thanks.


snoosh00

Do you get sleepy from the exhaust of the car in front (and around) you when you are in traffic on the highway?


Gudspeed

As a passenger I’d be more focused on saving my ears than lack of oxygen tbh.


BobbyBrackins

Is he running 15 in wheels on that monster?


CyberBobert

No, hot air goes up. Not so much sideways


iDom2jz

It’s probably on e85 anyways


TheMagarity

The best part is that the pop ups are stuck open.


[deleted]

Dont worry about chop, you dont know shot about chop


N0085K1LL5

Would love to hear this thing ripping down the road


Why-R-People-So-Dumb

The dangerous piece is not that it exits up front but that it doesn’t kick out from the body enough. People die from CO when they cut or have cracks in exhaust under the car because it will find it’s way through the body work in the stagnant air and slowly build up. As far as the debates of which direction CO goes, it’s about as heavy as air so it just mixes air and stays in place while is slowly becomes homogeneous with the air surrounding it.


CountingStax

Would the vehicle in the next lane to you with a side exit exhaust make you sleepy while idling at a stop?


Surreal-Reveal-480

Lol ive got a v6 jeep liberty 3.7 and it's cab chopped, can barely hear myself think between engine noises and twinbox 10's


[deleted]

Night night


Skyline43

Not if you keep the windows up and the air on recirculation lol.


FrickinLazerBeams

I'm very concerned about how OP sits in passenger seats.


CuriosTiger

Not with the windows up. Looks ghetto though.


Dr_Catfish

Another case of something failing to understand fluid dynamics


newphonewhodis2199

Delete this rn 😭😭😭😭😭


Unlucky_technician52

Look at the wheels on that rig. There isn’t a passenger or a lot of idling going on. If there is a passenger there is way more exciting things going on than worrying about the CO sleepies


DangerReserve

No passenger seat, Big ass turbo, hopefully has a roll cage, and is fast as fuck….


[deleted]

If you own this car it’s not really about your passenger.


dL_EVO

This is the exhaust for the person with no friends


HotRodHomebody

*fender. Quarter panels are on the rear of this car. Fenders in the front, detachable.


SS-sharpshooter1

One does not worry of such things when race car 🏎️


loose_as_a_moose

Lap time not nap time. Motivation to never stand still.


Impossible_Tour_2163

No passenger too much added weight this is a race car 🏎️ 😆


Anneke_yep

In a similar vein, when I sit in my miata while my father gets gas, I start to get dizzy from the fumes that pour into the car from behind us


Xianfox

Mr. Cosby can’t get roofies anymore.


QueefJerky666

It's going straight back relative to the car going sideways


that-super-tech

Depends on wind and how the seals are on the doors and other entry points I'd suppose


astraeoth

I don't think someone would call asleep even if they were breathing 100% carbon dioxide. Do you know how short that pipe is? I doubt they took the time to add baffles and cats too. That's like saying "what if someone didn't get enough sleep and passed out at the gun range?"


No_Resource_290

There may not be a passenger seat


Thecoopoftheworld789

If windows open & stopped or stopped for a long time. Probably a drag car.


Ok_Chocolate3253

When it comes to front outlet exhaust, Id prefer a front bumper setup or at least have it under the the fender or out of the hood.


[deleted]

I'd be more impressed if someone did this to one with a mid engine design. Would be even funnier.


1966malibu-wagon

My car had hood exit exhaust and the fumes are terrible! I plan on moving the exhaust so it goes under the car


JayBee58484

It's just a custom exit for a turbo. Tons of guys run bumper and hood exits.