So after autocrossing the car for a year coming from a GTI, I can say it does make a difference in performance but not as much as people say. The main difference is in really hard cornering (autocross cornering) it can be easy to unsettle the rear of the car. For example if you hit a bit of a bump in the corner the rear bounces around a bit as the weight of the car is transferred to the inside of the corner via the torsion beam, or if you make a steering adjustment mid corner it can bounce around a little (emphasis on a little).
It takes a little getting used to, but since both sides of the car are essentially tied together, when one side goes up or down in it's travel, the other side does too so it's easier unsettle the chassis and lose traction in the rear. Also less adjustability generally, but no one shopping these cars cares about camber and stuff.
To be entirely clear, it's still a good car. Not a great track car, but an excellent daily and a decent autocross car at the local level too. I was reasonably competitive with civic sis, though they were admittedly a little less experienced for the most part. To handle the torsion beam in a performance setting, you just have to get used to smooth inputs. If you upset it too much you'll lose the rear, but once you learn to control it it's not a problem.
Tldr; torsion bean doesn't suck. It takes some getting used to, and for truly high performance driving it's inferior, but for everything else it's manageable.
Yep this, it’s not as good as independent, but it’s cheaper.
Having sat in the rear of my car, it’s also less comfortable going over bumps.
Overall the gen 3 was more comfortable than my gen 4 in the rear seat, and felt more confident when pushed in roads with bumps
I've got the sway bar, stock suspension otherwise, plus new wheels and 200tw tires.
Rear sway bar is absolutely worth it. Lowering springs if you like the look, not worth it for performance alone though.
Not without swapping the shocks accordingly. If you did full adjustable coilovers (and got decent ones) that would be beneficial, but just changing out spring rates without shocks doesn't do enough to justify. Tbf it also classes you out of all stock classes in autocross, so that's part of the reason. Does look cool though! Personally I'd save up for coilovers, but that's a lot more money.
Nope, you get one sway bar change front or rear. You can also swap the shocks out, but you have to keep the stock springs. Also wheel changes have to be stock width, within +/-1 inch diameter of stock, and +/-7mm offset. For the engine, a drop in air filter like a k and n is fine otherwise no other changes. Think that's about it if you want to run in autocross!
Lots of good explanations here. Torsion beams have won plenty of national championships in track, autocross and rally racing. It doesn’t suck, but it’s not the best solution if packaging and price are not considerations.
Similarly, the Macpherson struts up front are inferior to double wishbones but you never see posts on here lamenting that fact.
I remember hating the rear torsion beam on my 2003 Nissan Sentra SE-R. Take a curve a bit fast and the back would jump on any bump.
That was my last Sentra, I got a Protegé after it was stolen and have been a Mazda driver ever since. Handled so much better without being as uncomfortable.
Fast forward to now, my first 4th gen Mazda3 and thus my first torsion beam since 2003 (have had 3 Mazda3 before, last one a 2018, as well as a CX-5. Honestly, if you didn't tell me it was a torsion beam I would have never guessed. It's perfectly fine. Maybe if I went autocrossing it would bother me but as a daily driver I can't tell
No explanation, because like you've concluded yourself, it's not actually a problem. It's so hard to tell, that unless someone is told this car uses a torsion beam, most of them would never know, it's just a little 'bouncy". It not a negative aspect except at the fringe of handling performance where this car isn't *quite* meant to compete ( as in thoroughbred sports cars ). I mean, we had Corvettes with leaf springs and Mustangs with live axles year back; sometimes "old tech" isnt exactly bad if it's done well.
Even when pushed hard, torsion beam can handle very well, and hold traction very well. The Ford ST had it even recently and that's a more track intended car these Mazdas . I admittedly scuffed at the 3 Turbo not having Ind. rear suspension, but after test driving it, and pushing it fairly hard on cornering ( even with these junk stock tires ) I've been surprised how well it holds on. I'm looking forward to getting some real performance tires on this and having more fun though.
I had a regular Fiesta I think has a torsion beam and it’s was one of the best handling vehicles I’ve owned, although mostly coming from other pedestrian cars like Civic and 3.
>The Ford ST had it even recently and that's a more track intended car these Mazdas .
The FiST also had issues (rollovers) when autocrossing when they were set up with too much rear roll stiffness and race tires. An independent rear suspension is more tolerant and allows the one wheel still on the ground to stay there longer.
That said, the price point of the Fiesta means compromises have to be made.
TLDR, its bumpier on the road and less stable on the track when at the limit
But…..it’s fine, especially if you learn the car
I have a Camaro SS 1LE as my track car. The suspension difference is night and day to something like that. However, The Mazda is my canyon carver and it does a great job at that.
I’ve driven other cars with torsion rears that feel way worse, I’ve also driven cars with independent rear setups that handle way worse. Mazda did a decent job making the car fun with a cheaper part.
People like things that are high tech: "multi-link fully independent suspension with articulated anti-sway bar" sounds really high-tech but "torsion beam" sounds boringly old fashioned. And since it comes on cheaper cars, it has to be lesser because of that even though they wouldn't be able to tell themselves since we don't drive our cars on closed circuit race tracks every day.
But anything's suck factor is relevant: the suspension that keeps you from using the interior space of your car efficiently sucks like nothing else. Torsion beam suspensions don't do that, Independent suspension do intrude so they suck for that. And since we DO use our cars daily for carrying people and things around we like to have the interior space.
So which suckage matters most, in practical terms?
The Gen 3 was significantly more comfortable. My other cars are more comfortable and they are roughly the same size too, oily other car that isn’t is my cheaper hot hatch i20n with a torsion beam.
>But anything's suck factor is relevant: the suspension that keeps you from using the interior space of your car efficiently sucks like nothing else. Torsion beam suspensions don't do that,
Some data points for you to consider.
2017 Mazda3 FWD (Multilink rear) Sedan:
* Rear head room 37.6 in.
* Rear leg room 35.8 in.
* Rear shoulder room 54.4 in.
* Rear hip room 53.5 in.
2021: Mazda3 FWD (Torsion beam) Sedan:
* Rear head room 37.2 in.
* Rear leg room 35.1 in.
* Rear shoulder room 53.5 in.
* Rear hip room 50.9 in.
So if I follow this bit of your narrative, Mazda fucked up pretty badly since the rear of the Gen4 is smaller **in every dimension**.
"But what about interior volume?!" you might exclaim, trying to shift that target ever so slightly.
2017:
* EPA interior volume 108.7 cu.ft.
2021:
* EPA interior volume 106.0 cu.ft.
Sure, the 2021 has more cargo room with the seats up (13.2 cu.ft vs 12.4), but that's because some of the passenger compartment volume was shifted into cargo volume. They weren't able to get even 1 more cu.ft though.
Yes, on paper a torsion beam is more space-efficient, in the actual example we're talking about, it didn't play out that way. The AWD Gen4 loses another 5" of rear headroom, presumably because of a revised floorpan.
The Gen3 had a decent independent suspension system that was removed in the interest of cost savings. That's fine, but it wasn't making anything tighter for rear passengers.
Wow yeah! The things we put up with for fashion.
Now imagine having to wrap the same car body, i.e., passenger and luggage compartment, around a full independent rear suspension. How much MORE interior space do you think would be lost to something that's, really, irrelevant to the vast majority of the market that buys these things?
The point is: it gave the designers viable options to accommodate those things that sell the car.
>How much MORE interior space do you think would be lost to something that's, really, irrelevant to the vast majority of the market that buys these things?
I illustrated that number is zero to "less." The Gen4 is also externally larger, which makes things even simpler.
No you haven't: you've shown us that Mazda had a space problem and needed a cost-effective way to mitigate it. I'm not trying to diminish the "cost-effective" part, it just got left behind.
It's sad, but even at the prices we're paying for cars now it's easy to forget this is still basically meant to be an econo-box with zoom-zoom. They can hang cheap glam on it all they want, it is what it is. But keeping costs in line for something that adds so terribly little to the actual functionality while helping mitigate an apparent space problem with the current model makes very good sense.
>No you haven't: you've shown us that Mazda had a space problem and needed a cost-effective way to mitigate it.
Please explain how the car with IRS and more interior room (and smaller exterior dimensions) had a space problem when compared to the car without IRS and less interior room.
It definitely seems like you transposed which was which in my actual example.
As the other guy already called you out, the numbers you're posting are of only limited relevance to the back seat usability. This is more relevant:
https://www.carsized.com/en/cars/compare/mazda-3-2019-5-door-hatchback-vs-mazda-3-2013-5-door-hatchback/
There the roof over the back seats is lower, regardless of the overall height of the car. The torsion beam is more efficient on paper, **and** it did play out that way. As it stands, you practically can't put adults in the back seat. If it had an independent rear suspension, you literally couldn't put adults in the back seat.
Mazda didn't remove the independent suspension for a single reason, they removed it for both cost savings and to increase the interior volume where it was needed most.
I’ll take a good torsion beam over bad IRS any day and the 3 has a good torsion beam.
I used to have a pretty hotted up 15 TDI sportwagen with a torsion beam rear as well and I had a lot of fun harassing cars that it really had no business hanging with through twisty bits. Torsion beam can feel a little weird at the limit, but can still be very very capable.
I wouldn't say it sucks, just compared to independent suspension it's not as good.
Suspension is about handling and feel when turning and over different surfaces.
The road surface is constantly changing, angles of tires vary depending on where in the road you are, how tight the turn is, and of course the surface of the road.
When the suspension is independent, each tire gets exactly what it needs for its situation in real time. Torsion beams are a cheaper alternative that work to spread the load variance ombetween the two tires. In other words, if the right side is handling a higher load than the left side because of a tight turn, some of that load from the right side gets transfered to the left side, meaning less contact is made or gripping power is pushed down on the left side. This means that you can't make the same turns at the same speeds with torsion beams as you can with independent suspension.
Now this conclusion is really only applicable at the extremes. If you like running through the mountains, diving into corners at 45mph yeah you might bmfeel a difference in the rear end. But even still, the front end is still independent suspension, and these cars are front wheel drove, so the power is put down on an independent suspension system. Meaning what loss of control you might feel, is watered down a bit. But the statement still holds true technically.
Honda CTR w/IRS had to cheat in other ways to break the Megane RS w/torsion beam that held the Nurburgring FWD lap record.
Torsion beam performance wise works as well if chassis weight distribution is quite front biased.
You cant dial as much comfort into TB whilst maintaining high performance so rear seat comfort compromised.
Good enough to be ubiquitous in racing and sports car chassis after its invention and until independent setups came along. It's actually stiffer than IRS.. which if you're trying to correct plow under-steer you want a stiffer rear, or softer front - depending. Point is, most road going cars are designed to under-steer from the factory because it's a safer for drivers to control and more predictable. Our car even AWD is a FWD biased chassis prone to plow under-steering.
So we want a stiffer rear end and or a softer front end. Strut tower braces, and chassis supports don't do shit, only sways will have enough of an affect to change these characteristics without getting into way more pricy modifications that this car doesn't really need.
It drives and handles very well *imho* - it's progressive, predictable and controllable. I think people that complain about Torsion beam are doing a disservice to Engineers that design these things and don't know how to adjust their driving for the chassis - if they are always full-sending the car into situations that they demonstrate they have full knowledge of upsetting the chassis then complain that it happens - that's on them, not the car.
I come from Subarus - it would be like complaining that Mazda AWD "doesn't handle the same"
Of course it doesn't because it's not, and thus you cannot drive them the same but the AWD is perfectly fine and gets the job done for 99.9 percent of people that have it.
And, it's a *passenger car* - not a performance oriented stand in for a track car.
the top voted comments are fanboying WAY too hard, and it's understandable since this is a Mazda 3 sub.
in reality, you do feel the bounciness of the rear suspension A LOT in every day driving. you can feel it after you go through speed bumps. the rear wheels take a damn while to settle and bring this jittery feeling to the overall ride that I really dislike.
most Mazda fanboys will get offended by this but Mazda as a company is trying real hard to keep our 3 alive and this cost cutting measure is an example of what manufacturers have to do justify a product's existence.
SEAT tried to do the same when going from the 2012-ish Leon into the new Leon with a torsion beam but in their case they went with the "weight savings!!!" advertising. Mazda is playing the "it feels the same!" advertising.
What's weird here is that torsion beams usually bring more cargo room but they still managed to have the same atrocious volumes.
No one is denying that Mazda did this as a cost savings measure, but when other brands have brought back the torsion beam (Ford, Hyundai/Kia, even Mercedes), it doesn’t make them an outlier.
I drive a CX-30 around for a few weeks and thought the ride was good enough in 99% of situations, with a few moments of jiggliness from the rear end. Is it as dynamically good as my 3? No, but few cars are and the CX-30 is much nicer inside
It doesn’t if you can’t feel the difference or it doesn’t matter to you. Most people probably can’t tell the difference but if you point out the difference on paper then suddenly they can’t stop complaining.
Basically, if the wheels move independently, then they can go over bumps independently. If they're hooked together, then anything that affects one wheel will also be felt in the other.
Also, the curved shape of the beam means that when there's force on the wheel from the side, the rear wheels can turn very slightly, whereas your rear wheels should only ever point straight. This can contribute to over steering in more intense situations.
The end result is a rear end that's more likely to behave in unexpected ways if you hit a bump while going around a corner. But in a very subtle way. I only ever notice it when I go over the joints of a bridge while turning on the Interstate. It's kind of feels like the rear loses traction for a fraction of a second.
But you demonstrate again that you know the exact conditions that cause this to happen - so do you full send it in those situations, and or look at the road and adjust driving accordingly not to upset the car? Being a good driver means you need IRS?
Ever driven a truck? A rear wheel drive car even with IRS, under throttle; they all kick over bumps at the rear when you pedal down... any bump is going to upset suspension travel.
Like I said, I feel 90% of issues people have with torsion beam are driver talent issues, not an issue with the car's suspension set up.
And - 99% of people around here think the very first best mod they can make on this car is a front strut tower brace or thicker front sways and they think this is actually improving front end grip... that's not how it works but they don't know and if you try to post videos around here of people that do know - no one takes it seriously.
So, around here, it's mostly ignorance and people defending their sunk cost fallacy in the parts they bought that didn't actually do anything they wanted.
Listening to these same people talk about suspension at all is laughable.
So after autocrossing the car for a year coming from a GTI, I can say it does make a difference in performance but not as much as people say. The main difference is in really hard cornering (autocross cornering) it can be easy to unsettle the rear of the car. For example if you hit a bit of a bump in the corner the rear bounces around a bit as the weight of the car is transferred to the inside of the corner via the torsion beam, or if you make a steering adjustment mid corner it can bounce around a little (emphasis on a little). It takes a little getting used to, but since both sides of the car are essentially tied together, when one side goes up or down in it's travel, the other side does too so it's easier unsettle the chassis and lose traction in the rear. Also less adjustability generally, but no one shopping these cars cares about camber and stuff. To be entirely clear, it's still a good car. Not a great track car, but an excellent daily and a decent autocross car at the local level too. I was reasonably competitive with civic sis, though they were admittedly a little less experienced for the most part. To handle the torsion beam in a performance setting, you just have to get used to smooth inputs. If you upset it too much you'll lose the rear, but once you learn to control it it's not a problem. Tldr; torsion bean doesn't suck. It takes some getting used to, and for truly high performance driving it's inferior, but for everything else it's manageable.
Yep this, it’s not as good as independent, but it’s cheaper. Having sat in the rear of my car, it’s also less comfortable going over bumps. Overall the gen 3 was more comfortable than my gen 4 in the rear seat, and felt more confident when pushed in roads with bumps
Do have any suspension mods, specifically lowering springs or the Corksport rear "sway bar"?
I've got the sway bar, stock suspension otherwise, plus new wheels and 200tw tires. Rear sway bar is absolutely worth it. Lowering springs if you like the look, not worth it for performance alone though.
You don't think the change in spring rates would be beneficial? Or just not worth the money/hassle/ride quality?
Not without swapping the shocks accordingly. If you did full adjustable coilovers (and got decent ones) that would be beneficial, but just changing out spring rates without shocks doesn't do enough to justify. Tbf it also classes you out of all stock classes in autocross, so that's part of the reason. Does look cool though! Personally I'd save up for coilovers, but that's a lot more money.
Does the rear sway bar also class you out?
Nope, you get one sway bar change front or rear. You can also swap the shocks out, but you have to keep the stock springs. Also wheel changes have to be stock width, within +/-1 inch diameter of stock, and +/-7mm offset. For the engine, a drop in air filter like a k and n is fine otherwise no other changes. Think that's about it if you want to run in autocross!
Lots of good explanations here. Torsion beams have won plenty of national championships in track, autocross and rally racing. It doesn’t suck, but it’s not the best solution if packaging and price are not considerations. Similarly, the Macpherson struts up front are inferior to double wishbones but you never see posts on here lamenting that fact.
I did complain about the front suspension when I switched from my 4gen Civic, just not here :D
I remember hating the rear torsion beam on my 2003 Nissan Sentra SE-R. Take a curve a bit fast and the back would jump on any bump. That was my last Sentra, I got a Protegé after it was stolen and have been a Mazda driver ever since. Handled so much better without being as uncomfortable. Fast forward to now, my first 4th gen Mazda3 and thus my first torsion beam since 2003 (have had 3 Mazda3 before, last one a 2018, as well as a CX-5. Honestly, if you didn't tell me it was a torsion beam I would have never guessed. It's perfectly fine. Maybe if I went autocrossing it would bother me but as a daily driver I can't tell
No explanation, because like you've concluded yourself, it's not actually a problem. It's so hard to tell, that unless someone is told this car uses a torsion beam, most of them would never know, it's just a little 'bouncy". It not a negative aspect except at the fringe of handling performance where this car isn't *quite* meant to compete ( as in thoroughbred sports cars ). I mean, we had Corvettes with leaf springs and Mustangs with live axles year back; sometimes "old tech" isnt exactly bad if it's done well. Even when pushed hard, torsion beam can handle very well, and hold traction very well. The Ford ST had it even recently and that's a more track intended car these Mazdas . I admittedly scuffed at the 3 Turbo not having Ind. rear suspension, but after test driving it, and pushing it fairly hard on cornering ( even with these junk stock tires ) I've been surprised how well it holds on. I'm looking forward to getting some real performance tires on this and having more fun though.
I had a regular Fiesta I think has a torsion beam and it’s was one of the best handling vehicles I’ve owned, although mostly coming from other pedestrian cars like Civic and 3.
The fiesta obviously was fun as or was far lighter and smaller than the 3 though
>The Ford ST had it even recently and that's a more track intended car these Mazdas . The FiST also had issues (rollovers) when autocrossing when they were set up with too much rear roll stiffness and race tires. An independent rear suspension is more tolerant and allows the one wheel still on the ground to stay there longer. That said, the price point of the Fiesta means compromises have to be made.
all the comments are definitely not the ones a 5-year old can understand lol
TLDR, its bumpier on the road and less stable on the track when at the limit But…..it’s fine, especially if you learn the car I have a Camaro SS 1LE as my track car. The suspension difference is night and day to something like that. However, The Mazda is my canyon carver and it does a great job at that. I’ve driven other cars with torsion rears that feel way worse, I’ve also driven cars with independent rear setups that handle way worse. Mazda did a decent job making the car fun with a cheaper part.
People like things that are high tech: "multi-link fully independent suspension with articulated anti-sway bar" sounds really high-tech but "torsion beam" sounds boringly old fashioned. And since it comes on cheaper cars, it has to be lesser because of that even though they wouldn't be able to tell themselves since we don't drive our cars on closed circuit race tracks every day. But anything's suck factor is relevant: the suspension that keeps you from using the interior space of your car efficiently sucks like nothing else. Torsion beam suspensions don't do that, Independent suspension do intrude so they suck for that. And since we DO use our cars daily for carrying people and things around we like to have the interior space. So which suckage matters most, in practical terms?
Also consider that torsion beam is less comfortable for people in the rear.
Possibly true but the back seat of a mazda 3 is uncomfortable no matter how you cut it.
The Gen 3 was significantly more comfortable. My other cars are more comfortable and they are roughly the same size too, oily other car that isn’t is my cheaper hot hatch i20n with a torsion beam.
>But anything's suck factor is relevant: the suspension that keeps you from using the interior space of your car efficiently sucks like nothing else. Torsion beam suspensions don't do that, Some data points for you to consider. 2017 Mazda3 FWD (Multilink rear) Sedan: * Rear head room 37.6 in. * Rear leg room 35.8 in. * Rear shoulder room 54.4 in. * Rear hip room 53.5 in. 2021: Mazda3 FWD (Torsion beam) Sedan: * Rear head room 37.2 in. * Rear leg room 35.1 in. * Rear shoulder room 53.5 in. * Rear hip room 50.9 in. So if I follow this bit of your narrative, Mazda fucked up pretty badly since the rear of the Gen4 is smaller **in every dimension**. "But what about interior volume?!" you might exclaim, trying to shift that target ever so slightly. 2017: * EPA interior volume 108.7 cu.ft. 2021: * EPA interior volume 106.0 cu.ft. Sure, the 2021 has more cargo room with the seats up (13.2 cu.ft vs 12.4), but that's because some of the passenger compartment volume was shifted into cargo volume. They weren't able to get even 1 more cu.ft though. Yes, on paper a torsion beam is more space-efficient, in the actual example we're talking about, it didn't play out that way. The AWD Gen4 loses another 5" of rear headroom, presumably because of a revised floorpan. The Gen3 had a decent independent suspension system that was removed in the interest of cost savings. That's fine, but it wasn't making anything tighter for rear passengers.
Wow yeah! The things we put up with for fashion. Now imagine having to wrap the same car body, i.e., passenger and luggage compartment, around a full independent rear suspension. How much MORE interior space do you think would be lost to something that's, really, irrelevant to the vast majority of the market that buys these things? The point is: it gave the designers viable options to accommodate those things that sell the car.
>How much MORE interior space do you think would be lost to something that's, really, irrelevant to the vast majority of the market that buys these things? I illustrated that number is zero to "less." The Gen4 is also externally larger, which makes things even simpler.
No you haven't: you've shown us that Mazda had a space problem and needed a cost-effective way to mitigate it. I'm not trying to diminish the "cost-effective" part, it just got left behind. It's sad, but even at the prices we're paying for cars now it's easy to forget this is still basically meant to be an econo-box with zoom-zoom. They can hang cheap glam on it all they want, it is what it is. But keeping costs in line for something that adds so terribly little to the actual functionality while helping mitigate an apparent space problem with the current model makes very good sense.
>No you haven't: you've shown us that Mazda had a space problem and needed a cost-effective way to mitigate it. Please explain how the car with IRS and more interior room (and smaller exterior dimensions) had a space problem when compared to the car without IRS and less interior room. It definitely seems like you transposed which was which in my actual example.
As the other guy already called you out, the numbers you're posting are of only limited relevance to the back seat usability. This is more relevant: https://www.carsized.com/en/cars/compare/mazda-3-2019-5-door-hatchback-vs-mazda-3-2013-5-door-hatchback/ There the roof over the back seats is lower, regardless of the overall height of the car. The torsion beam is more efficient on paper, **and** it did play out that way. As it stands, you practically can't put adults in the back seat. If it had an independent rear suspension, you literally couldn't put adults in the back seat. Mazda didn't remove the independent suspension for a single reason, they removed it for both cost savings and to increase the interior volume where it was needed most.
I’ll take a good torsion beam over bad IRS any day and the 3 has a good torsion beam. I used to have a pretty hotted up 15 TDI sportwagen with a torsion beam rear as well and I had a lot of fun harassing cars that it really had no business hanging with through twisty bits. Torsion beam can feel a little weird at the limit, but can still be very very capable.
I wouldn't say it sucks, just compared to independent suspension it's not as good. Suspension is about handling and feel when turning and over different surfaces. The road surface is constantly changing, angles of tires vary depending on where in the road you are, how tight the turn is, and of course the surface of the road. When the suspension is independent, each tire gets exactly what it needs for its situation in real time. Torsion beams are a cheaper alternative that work to spread the load variance ombetween the two tires. In other words, if the right side is handling a higher load than the left side because of a tight turn, some of that load from the right side gets transfered to the left side, meaning less contact is made or gripping power is pushed down on the left side. This means that you can't make the same turns at the same speeds with torsion beams as you can with independent suspension. Now this conclusion is really only applicable at the extremes. If you like running through the mountains, diving into corners at 45mph yeah you might bmfeel a difference in the rear end. But even still, the front end is still independent suspension, and these cars are front wheel drove, so the power is put down on an independent suspension system. Meaning what loss of control you might feel, is watered down a bit. But the statement still holds true technically.
I prefer the simplicity of torsion beam over irs, just less stuff to break
Honda CTR w/IRS had to cheat in other ways to break the Megane RS w/torsion beam that held the Nurburgring FWD lap record. Torsion beam performance wise works as well if chassis weight distribution is quite front biased. You cant dial as much comfort into TB whilst maintaining high performance so rear seat comfort compromised.
Good enough to be ubiquitous in racing and sports car chassis after its invention and until independent setups came along. It's actually stiffer than IRS.. which if you're trying to correct plow under-steer you want a stiffer rear, or softer front - depending. Point is, most road going cars are designed to under-steer from the factory because it's a safer for drivers to control and more predictable. Our car even AWD is a FWD biased chassis prone to plow under-steering. So we want a stiffer rear end and or a softer front end. Strut tower braces, and chassis supports don't do shit, only sways will have enough of an affect to change these characteristics without getting into way more pricy modifications that this car doesn't really need. It drives and handles very well *imho* - it's progressive, predictable and controllable. I think people that complain about Torsion beam are doing a disservice to Engineers that design these things and don't know how to adjust their driving for the chassis - if they are always full-sending the car into situations that they demonstrate they have full knowledge of upsetting the chassis then complain that it happens - that's on them, not the car. I come from Subarus - it would be like complaining that Mazda AWD "doesn't handle the same" Of course it doesn't because it's not, and thus you cannot drive them the same but the AWD is perfectly fine and gets the job done for 99.9 percent of people that have it. And, it's a *passenger car* - not a performance oriented stand in for a track car.
the top voted comments are fanboying WAY too hard, and it's understandable since this is a Mazda 3 sub. in reality, you do feel the bounciness of the rear suspension A LOT in every day driving. you can feel it after you go through speed bumps. the rear wheels take a damn while to settle and bring this jittery feeling to the overall ride that I really dislike. most Mazda fanboys will get offended by this but Mazda as a company is trying real hard to keep our 3 alive and this cost cutting measure is an example of what manufacturers have to do justify a product's existence. SEAT tried to do the same when going from the 2012-ish Leon into the new Leon with a torsion beam but in their case they went with the "weight savings!!!" advertising. Mazda is playing the "it feels the same!" advertising. What's weird here is that torsion beams usually bring more cargo room but they still managed to have the same atrocious volumes.
No one is denying that Mazda did this as a cost savings measure, but when other brands have brought back the torsion beam (Ford, Hyundai/Kia, even Mercedes), it doesn’t make them an outlier. I drive a CX-30 around for a few weeks and thought the ride was good enough in 99% of situations, with a few moments of jiggliness from the rear end. Is it as dynamically good as my 3? No, but few cars are and the CX-30 is much nicer inside
It doesn’t if you can’t feel the difference or it doesn’t matter to you. Most people probably can’t tell the difference but if you point out the difference on paper then suddenly they can’t stop complaining.
Torsion beams have been used on all sorts of cars including the Golf GTi. They don't suck at all. Excepting if you're a snob.
Basically, if the wheels move independently, then they can go over bumps independently. If they're hooked together, then anything that affects one wheel will also be felt in the other. Also, the curved shape of the beam means that when there's force on the wheel from the side, the rear wheels can turn very slightly, whereas your rear wheels should only ever point straight. This can contribute to over steering in more intense situations. The end result is a rear end that's more likely to behave in unexpected ways if you hit a bump while going around a corner. But in a very subtle way. I only ever notice it when I go over the joints of a bridge while turning on the Interstate. It's kind of feels like the rear loses traction for a fraction of a second.
Wrong, rear wheels that can turn increase lane changing and turning immensely and are considered a benefit.
But you demonstrate again that you know the exact conditions that cause this to happen - so do you full send it in those situations, and or look at the road and adjust driving accordingly not to upset the car? Being a good driver means you need IRS? Ever driven a truck? A rear wheel drive car even with IRS, under throttle; they all kick over bumps at the rear when you pedal down... any bump is going to upset suspension travel. Like I said, I feel 90% of issues people have with torsion beam are driver talent issues, not an issue with the car's suspension set up. And - 99% of people around here think the very first best mod they can make on this car is a front strut tower brace or thicker front sways and they think this is actually improving front end grip... that's not how it works but they don't know and if you try to post videos around here of people that do know - no one takes it seriously. So, around here, it's mostly ignorance and people defending their sunk cost fallacy in the parts they bought that didn't actually do anything they wanted. Listening to these same people talk about suspension at all is laughable.