[Tim603]

I cant find a straight answer for some reason. Will this bolt right up? I have an 27mm H&R E90 M3 front sway bar and want to put it on my E90 335i

Thanks for any assistance!

[Jaronbwall]

It's best to wait till you have a proper LSD before doing sway bars. If not I've read it turns your car into a three wheeler.

[feuer]

Originally Posted by Tim603

I cant find a straight answer for some reason. Will this bolt right up? I have an 27mm H&R E90 M3 front sway bar and want to put it on my E90 335i

Thanks for any assistance!

Yes, it will fit but you will need M3 swaybar bushings and mounting brackets. The swaybar links from the 335i fit just fine.

[Tim603]

Originally Posted by Jarronbwall

It's best to wait till you have a proper LSD before doing sway bars. If not I've read it turns your car into a three wheeler.

I am about to lower my car and do front/rear sway bars. I have heard that on the rear sway bar but not about the front, regardless I will let you all know the review!

Originally Posted by feuer

Yes, it will fit but you will need M3 swaybar bushings and mounting brackets. The swaybar links from the 335i fit just fine.

Nice!! Thanks for the help. In case anyone stumbles across this thread...the bushing brackets are 31352283037

[feuer]

Originally Posted by Jarronbwall

It's best to wait till you have a proper LSD before doing sway bars. If not I've read it turns your car into a three wheeler.

Read? I guess we could all do more of that. Three wheeeler? Sure, why not? I could use all the grip on the rear I can get, LSD or not. That is why OP is inquiring about front swaybar, not rear. Is RWD car.

[Tim603]

Originally Posted by feuer

Read? I guess we could all do more of that. Three wheeeler? Sure, why not? I could use all the grip on the rear I can get, LSD or not. That is why OP is inquiring about front swaybar, not rear. Is RWD car.

Yeah I'm not sure how a rear sway bar will make my car a three wheeler, nor how a LSD would bring me back to a 4 wheeler?

Anyways yes my car is RWD so I think the sway bars will help. Nonetheless I will surely let you guys know how I like it

[feuer]

Originally Posted by Tim603

Yeah I'm not sure how a rear sway bar will make my car a three wheeler, nor how a LSD would bring me back to a 4 wheeler?

Anyways yes my car is RWD so I think the sway bars will help. Nonetheless I will surely let you guys know how I like it

Front yes, rear no. On rwd. On fwd is oposite. LSD or not, does not matter. Do not waste money on the rear.
I have posted here great artivles with photos.

[Tim603]

Originally Posted by feuer

Front yes, rear no. On rwd. On fwd is oposite. LSD or not, does not matter. Do not waste money on the rear.
I have posted here great artivles with photos.

Really, so let's take traction out of the picture. Do you think a rear sway bar will help with handling/cornering say on a track?

[snaimpally]

Originally Posted by Tim603

I cant find a straight answer for some reason.

A google search returns:
https://www.turnermotorsport.com/t-t...sway-bars.aspx

The OEM sway bars, including the M3, are all hollow. You are better of getting aftermarket (H&R, Eibach, etc.) sway bars as they are solid and heavier. You can buy an aftermarket set that includes both front and rear sway bars for close to the price of the M3 FSB alone.

Upgrading your sway bars without an LSD will not give you very much in the way of benefits. You are far better off saving your money and getting an LSD. An LSD was the first suspension upgrade I made and it was by far the best one.

[Cloud9blue]

Originally Posted by snaimpally

A google search returns:
https://www.turnermotorsport.com/t-t...sway-bars.aspx

The OEM sway bars, including the M3, are all hollow. You are better of getting aftermarket (H&R, Eibach, etc.) sway bars. You can buy both front and rear sway bars for close to the price of the M3 FSB.

Stiffer does not equal to better when it comes to sway bar... We are not talking about your erectile dysfunction here...

E9x M3 front bar is plenty stiff for cars running on street tires.

[justpete]

Originally Posted by Tim603

Really, so let's take traction out of the picture. Do you think a rear sway bar will help with handling/cornering say on a track?

No, a stiffer rear ARB will decrease traction and ultimately increase snap oversteer. Track/race cars run without rear ARBs or at best very light ones.

A stiff bar will cause the inside wheel in a turn to lift and without an LSD you'll lose power to the road, an LSD will help steer the torque back to the wheel on the road. But it's not a correction to putting the wrong rear ARB on the car.

[feuer]

Originally Posted by Tim603

Really, so let's take traction out of the picture. Do you think a rear sway bar will help with handling/cornering say on a track?

What part from front yes rear no you did not get? Forget about the rear swaybar.

[Tim603]

Originally Posted by justpete

No, a stiffer rear ARB will decrease traction and ultimately increase snap oversteer. Track/race cars run without rear ARBs or at best very light ones.

A stiff bar will cause the inside wheel in a turn to lift and without an LSD you'll lose power to the road, an LSD will help steer the torque back to the wheel on the road. But it's not a correction to putting the wrong rear ARB on the car.

This is what I was looking for, thanks for the info man! Looks like I will NOT be getting a rear sway bar lol

Oh and the front one I have for the M3 is indeed H&R in case you all were wondering

[justpete]

Originally Posted by Tim603

This is what I was looking for, thanks for the info man! Looks like I will NOT be getting a rear sway bar lol

Oh and the front one I have for the M3 is indeed H&R in case you all were wondering

Happy to help!

[The HACK]

Originally Posted by snaimpally

A google search returns:
https://www.turnermotorsport.com/t-t...sway-bars.aspx

The OEM sway bars, including the M3, are all hollow. You are better of getting aftermarket (H&R, Eibach, etc.) sway bars as they are solid and heavier. You can buy an aftermarket set that includes both front and rear sway bars for close to the price of the M3 FSB alone.

Upgrading your sway bars without an LSD will not give you very much in the way of benefits. You are far better off saving your money and getting an LSD. An LSD was the first suspension upgrade I made and it was by far the best one.

There are some really BAD advices being given on this forum. BAAAAAAAAAAD advices.

Like EPICLY bad. 95% of all "advices" given in this forum, on a quick browse, are just shockingly bad and absolutely wrong. As in given by people who should have no right giving any sort of advice. Like laymen giving out medical advice about complicated medical procedure bad.

Throwing out the comment about rear sways needing LSD, which on face value is absolutely invalid without further extrapolation, the idea that "solid," heavier bars are superior to hollow bars is simply idiotic and screams "I have no idea what I am talking about, but I still must sound like an expert because it is the intarweb." Oh. My. Gawd.

People, if you don't know what you're doing, don't pretend to be an expert. I know it's the intarweb so everything you say must be right.

I'll preface this by saying I am not an expert. I have zero engineering background besides some applied physics courses taken in college as part of my required classes for my major. I understand automotive engineering about as much as the next idiot that post in this forum. So take what I have to say with giant grains of salt.

Do not believe ANYTHING you read on these forums. Anything. That includes the crap that's coming out of my keyboard right now. Do your own research. Ask experts. Ask your mechanic. Ask people who actually know what they're talking about in real life. Because it's easy to spout off bullsh*t on the internet and look like an expert.

For instance, I can tell you that hollow swaybars are far superior to solid bars for multitude of reasons, such as:

http://physics.stackexchange.com/que...e-diameter-o-d

https://www.physicsforums.com/thread...lid-rod.37701/

And I quote:

a hollow cylinder is stronger than a rod of equal mass and the same material. A hollow cylinder with a bigger inside diameter is better. In the limit x→1x→1 the hollow cylinder is twice as strong.

See? I can quote some random sh*t and make my post look like an expert post too. I even have links!

The TRUTH of the matter is, besides anyone giving anyone else "advice" on these forums, and anyone believing said advice, are all idiots...Is this.

There are no hard, set rules wrt to swaybar upgrades to follow. If you think about it, a hollow bar made of the same material and of the same weight as a solid bar can be as much as 2X as stiff in torsional rigidity. However, that's ignoring the fact that the hollow bar would likely have to be slightly larger in diameter in order to be the same material and WEIGHT. The TRUTH is, a hollow bar of a slightly larger outer diameter is as stiff, or can be stiffer, than a solid bar of a slightly smaller diameter, but weight SIGNIFICANTLY less.

I'm going to just pull some number out of my magical hat, also known as my ass. This is PURELY for example purposes, these numbers are by no means real. Remember, I am no material scientist/engineer.

Let's say, you have a solid bar of 30mm diameter vs a hollow bar of 32mm outer diameter and a 16mm inner diameter. In this example, the 32mm bar can be as much as 60% of the weight of the 30mm bar while being 5% stiffer than the 30mm bar. While that 3 lbs of weight saving is insignificant in the grand scheme of things, it IS stiffer, it is larger, and it is BETTER because it weigh less because race car.

From a marketing perspective (my expertise...That I can proudly say), 2/3 the material cost, better performance, and you can probably charge MORE? The hollow 32mm bar is definitely superior to the solid bar from an engineering, operations, and marketing perspective to the solid 30mm bar.

But in all reality...You are all asking the wrong questions. The real question is why do *I* want a better handling car, and is upgrading the swaybar the best way to go about doing it. If you're not asking those two questions, you won't get the right answers. The truth is, if you're upgrading the handling of the car because race car, swaybar is the LAST upgrade I'd touch. If you're upgrading the handling of the car because you like to go around corners fast, swaybar is not the first upgrade I'd touch. If you're upgrading the handling of your car because you've got money burning a hole in your pocket? Swaybar is still not the first upgrade. If you're upgrading your car's handling because you're dying to join a community of enthusiasts that enjoys modifying their car, but don't really care one way or another if they truly are making their cars better? I might poke a swaybar with a 10' pole.

If all you care about is getting rid of body roll? Upgrade the swaybars.

Then ask yourself what did body roll did to you that makes you hate it that much.

[Tim603]

Originally Posted by The HACK

There are some really BAD advices being given on this forum. BAAAAAAAAAAD advices.

Like EPICLY bad. 95% of all "advices" given in this forum, on a quick browse, are just shockingly bad and absolutely wrong. As in given by people who should have no right giving any sort of advice. Like laymen giving out medical advice about complicated medical procedure bad.

Throwing out the comment about rear sways needing LSD, which on face value is absolutely invalid without further extrapolation, the idea that "solid," heavier bars are superior to hollow bars is simply idiotic and screams "I have no idea what I am talking about, but I still must sound like an expert because it is the intarweb." Oh. My. Gawd.

People, if you don't know what you're doing, don't pretend to be an expert. I know it's the intarweb so everything you say must be right.

I'll preface this by saying I am not an expert. I have zero engineering background besides some applied physics courses taken in college as part of my required classes for my major. I understand automotive engineering about as much as the next idiot that post in this forum. So take what I have to say with giant grains of salt.

Do not believe ANYTHING you read on these forums. Anything. That includes the crap that's coming out of my keyboard right now. Do your own research. Ask experts. Ask your mechanic. Ask people who actually know what they're talking about in real life. Because it's easy to spout off bullsh*t on the internet and look like an expert.

For instance, I can tell you that hollow swaybars are far superior to solid bars for multitude of reasons, such as:

http://physics.stackexchange.com/que...e-diameter-o-d

https://www.physicsforums.com/thread...lid-rod.37701/

And I quote:



See? I can quote some random sh*t and make my post look like an expert post too. I even have links!

The TRUTH of the matter is, besides anyone giving anyone else "advice" on these forums, and anyone believing said advice, are all idiots...Is this.

There are no hard, set rules wrt to swaybar upgrades to follow. If you think about it, a hollow bar made of the same material and of the same weight as a solid bar can be as much as 2X as stiff in torsional rigidity. However, that's ignoring the fact that the hollow bar would likely have to be slightly larger in diameter in order to be the same material and WEIGHT. The TRUTH is, a hollow bar of a slightly larger outer diameter is as stiff, or can be stiffer, than a solid bar of a slightly smaller diameter, but weight SIGNIFICANTLY less.

I'm going to just pull some number out of my magical hat, also known as my ass. This is PURELY for example purposes, these numbers are by no means real. Remember, I am no material scientist/engineer.

Let's say, you have a solid bar of 30mm diameter vs a hollow bar of 32mm outer diameter and a 16mm inner diameter. In this example, the 32mm bar can be as much as 60% of the weight of the 30mm bar while being 5% stiffer than the 30mm bar. While that 3 lbs of weight saving is insignificant in the grand scheme of things, it IS stiffer, it is larger, and it is BETTER because it weigh less because race car.

From a marketing perspective (my expertise...That I can proudly say), 2/3 the material cost, better performance, and you can probably charge MORE? The hollow 32mm bar is definitely superior to the solid bar from an engineering, operations, and marketing perspective to the solid 30mm bar.

But in all reality...You are all asking the wrong questions. The real question is why do *I* want a better handling car, and is upgrading the swaybar the best way to go about doing it. If you're not asking those two questions, you won't get the right answers. The truth is, if you're upgrading the handling of the car because race car, swaybar is the LAST upgrade I'd touch. If you're upgrading the handling of the car because you like to go around corners fast, swaybar is not the first upgrade I'd touch. If you're upgrading the handling of your car because you've got money burning a hole in your pocket? Swaybar is still not the first upgrade. If you're upgrading your car's handling because you're dying to join a community of enthusiasts that enjoys modifying their car, but don't really care one way or another if they truly are making their cars better? I might poke a swaybar with a 10' pole.

If all you care about is getting rid of body roll? Upgrade the swaybars.

Then ask yourself what did body roll did to you that makes you hate it that much.

Lol thanks for the info man, honestly I didn't look too much into the hollow/solid sway bar thing as I don't really care that much lol

Im going to start with coils and front sway bar and see how that goes. I already have wider wheels with aggressive tires and a strut bar so all these things should stiffen up the stupid body roll I am experiencing

Thanks again

[dicostal]

The only thing I do not like about the M3 sway bar is that it thins out at the center, where as the H&R for example is the same diameter across, thus I was thinking about going with the H&R one. OP when you are done with the install let me know the exact parts you got so I can make sure I get the correct ones.

Thanks!!!

[Tim603]

Originally Posted by dicostal

The only thing I do not like about the M3 sway bar is that it thins out at the center, where as the H&R for example is the same diameter across, thus I was thinking about going with the H&R one. OP when you are done with the install let me know the exact parts you got so I can make sure I get the correct ones.

Thanks!!!

Yeah the H&R One seems like a great choice. These are the parts I bought! I will definitely let you guys know how it goes

https://www.ecstuning.com/Search/Sit...2%20es2188379/

[justpete]

Originally Posted by dicostal

The only thing I do not like about the M3 sway bar is that it thins out at the center, where as the H&R for example is the same diameter across, thus I was thinking about going with the H&R one. OP when you are done with the install let me know the exact parts you got so I can make sure I get the correct ones.

Thanks!!!

Pretty sure they have engineers at BMW and that they didn't do this randomly. There's no reason at all to think a constant diameter is in any way "better". FWIW

[justpete]

Originally Posted by Tim603

Lol thanks for the info man, honestly I didn't look too much into the hollow/solid sway bar thing as I don't really care that much lol

Im going to start with coils and front sway bar and see how that goes. I already have wider wheels with aggressive tires and a strut bar so all these things should stiffen up the stupid body roll I am experiencing

Thanks again

Spring rates and ARB torsional rate are related, it's never a great idea to randomly mix them without knowing your roll center and desired roll rate and roll coupling. Better to choose spring rates front and rear since it's possible to make up for a softer bar with heavier rate springs. The ARB is something to do later once you know what you need. Save some money and don't worry about it now.

[dicostal]

Originally Posted by justpete

Spring rates and ARB torsional rate are related, it's never a great idea to randomly mix them without knowing your roll center and desired roll rate and roll coupling. Better to choose spring rates front and rear since it's possible to make up for a softer bar with heavier rate springs. The ARB is something to do later once you know what you need. Save some money and don't worry about it now.

That is another great point. I have the sport package with sport springs if I get the m3 sway bars (bmw or H&R) should I be changing springs or are stock springs ok? (I will reach out to Turner Motorsport for their advise and report back )

[dicostal]

Originally Posted by Tim603

Yeah the H&R One seems like a great choice. These are the parts I bought! I will definitely let you guys know how it goes

https://www.ecstuning.com/Search/Sit...2%20es2188379/

Thanks, good price!!!

I wonder whats the difference between the above and this one:

http://www.turnermotorsport.com/p-14...le-non-xi.aspx