[SSW]

After a long foot dragging delay, I just had 4 new TRW M3 front control arms installed in my 2008 E90. Handling is markedly improved w/the M3 control arms but there is still a bit of sway that I don't like.

So, I'm planning to add the E93 M3 28-24mm sway bar which the notes on Turner's site indicate would be the best compromise between the softer (by about 50%) E90/92 M3 26.5mm sway bar and stiffer (by about 300%) full-on solid H&R 27mm bar.

Has anyone here actually installed an E93 M3 bar in an E90/E92 and, if so, what has been your experience/observations before/after installation?

Yes. Do it. Worthwhile mod.

[Antetokounmpo]

you're just doing front? better do rear too otherwise it'll understeer even worse with just the front.

Originally Posted by Antetokounmpo

you're just doing front? better do rear too otherwise it'll understeer even worse with just the front.

No way...the bigger front bar, even on an otherwise stock car, will make a big difference when it comes to keeping the front end more flat in the twisties. We have the McPherson strut setup to thank for that

[Antetokounmpo]

Originally Posted by FCobra94

No way...the bigger front bar, even on an otherwise stock car, will make a big difference when it comes to keeping the front end more flat in the twisties. We have the McPherson strut setup to thank for that

More flat yes, but will also lose some grip at the front making the car understeer more. Adding a larger rear to the same percentage as the front keeps the same behavior as before with less roll and quicker transitions. I think one of the biggest misconceptions is stiffer and less roll means more grip which isn't really the case. As long as OP is running some negative camber there is no doubt in my mind it'd lead to more understeer even with Macp strut.

http://www.e90post.com/forums/showth...1242385&page=2

Although I haven't tracked my car, for street duty, the car certainly does NOT "understeer more." If those are the effects, then I am certainly not driving fast enough to notice....with my driving style, all I've seen are positive gains with this mod....as have most of the people in the link you posted above.

You'll find 3 trillion more peeps that will tell you going with a larger rear bar, with no LSD, ends up being bad news. IDK cuz I haven't tried it, but it makes sense.

The E93 M3 front bar is a perfect middle-of-the-road front sway for anyone that has no, or otherwise mild, suspension mods though....most anyone that actually has one installed will tell you the same.

I agree though, camber definitely makes more of a difference...but when it comes to bang for the buck for casual wrenchers, the bigger bar can't be beat.

[feuer]

Ok flame suit on lol
Rule of thumb for "solving" under steer with sway bars:
Fwd-upgrade rear sway bar
Rwd-upgrade front sway bar
Is about weight transfer.
Why else would m3 e93 have largest front sway bar?
AMG does the same on Mercedes.
Rear remains unchanged in some applications.
They just throw larger front sway bar.
Some race BMW don't even run rear sway bar.

[SSW]

Ok, thanks, guys!

I saw a used E93 M3 sway bar including bushings and brackets on eBay for $175 plus $20 shipping but the seller isn't willing to haggle.

So, I'm just going to buy a new OEM E93 M3 sway bar kit that includes OEM bushings, brackets and nuts for $343 with free shipping from ECS. It's about $150 more than the used one on eBay but the seller really doesn't know what year car it came out of and it's not enough more $ to worry about. I'll be getting all new parts which I'd prefer anyway.

Don't think there will be an understeer issue but, if there is, I'll just try lowering the rear tire pressure or reducing the rear toe-in settings slightly, which are supposed to help reduce understeer, before messing w/the rear sway bar and other rear suspension parts, which I really don't want to do.

[feuer]

SSW just buy the used sway bar. The $150 can go toward other parts or alignment.

[SSW]

Originally Posted by feuer

SSW just buy the used sway bar. The $150 can go toward other parts or alignment.

Nah.

Don't like dealing w/guys who aren't willing to accept a reasonable offer. Offered $175 including shipping which is just a $20 discount under his asking. If he wanted to really sell it, he would have accepted the offer.

I'd rather order a new kit from ECS (even at almost 2x the price) so that I know the parts are legit and complete (and can return/exchange them if there's a problem).

Still have to pay a couple hundred to have my shop install the bar -- I don't do any of my own work any more -- but I've thrown so much money at this car already (over $10k), a few more $'s really won't matter.

[Volasko]

I'm not going to get into a huge technical discussion about the differences, but my personal experience when upgrading JUST the front sway bar from and E93 M3 was more understeer. When driving aggressively in wet conditions it was actually quite scary how quick the front tires lost grip compared to stock sport sways.

Sure, everyone's experience will very depending on other mods involved, driving conditions, driving style, etc. The post below does a great job of explaining why that's the case (great overall thread in general actually):
http://www.1addicts.com/forums/showp...2&postcount=15

It's obvious that you can't just bolt on a stiffer bar, run some lame staggered tire setup with 225s up front, almost zero static camber, then assume that you'll be king of the auto-x that weekend...I wouldn't expect that of any singular suspension mod; E93 M3 sway bar included.

[matteblue3er]

E93 M3 bar is a bit stiff for E90. It will introduce snap oversteer.

I'd opt for rear subframe bushings over the rear bar personally

Originally Posted by matteblue3er

E93 M3 bar is a bit stiff for E90. It will introduce snap oversteer.

We're talking about front bars here dude, not rear...further more, lack of LSD will probably prevent any snap oversteer for most anyway.

[cpie168]

Has anyone got any experience with the ECS branded front bar? It's priced reasonably and I wonder how it performs.

Originally Posted by cpie168

Has anyone got any experience with the ECS branded front bar? It's priced reasonably and I wonder how it performs.

Given that the ECS version is a 28mm solid front bar, I imagine that you'd have to already have some serious suspension work to take advantage of it:
https://www.turnermotorsport.com/t-t...-e92-sway-bars

[cpie168]

What is considered serious suspension work? Would M3 front upper and lower arms count?

Originally Posted by cpie168

What is considered serious suspension work? Would M3 front upper and lower arms count?

No.

[SSW]

Originally Posted by matteblue3er

E93 M3 bar is a bit stiff for E90. It will introduce snap oversteer.

The E93 M3 bar is actually tapered from 28mm at the ends to 24mm in the center and it's tubular, not solid.

According to Turner, it's only about 13% stiffer than the stock E90 bar, as compared w/the the E90/92 M3 bar which is rated at about 7% stiffer than stock.

So, I really don't expect any major oversteer issues. If there are any, there are many simpler ways to deal with it than messing around with the rear end, which I've already said is something that I really don't want to do.

The new OEM E93 M3 bar/bolt kit that I ordered from ECS is due to arrive shortly. Will report on the results after it's installed.

[cpie168]

Looking forward to your report, SSW!

[Antetokounmpo]

Originally Posted by feuer

Ok flame suit on lol
Rule of thumb for "solving" under steer with sway bars:
Fwd-upgrade rear sway bar
Rwd-upgrade front sway bar
Is about weight transfer.
Why else would m3 e93 have largest front sway bar?
AMG does the same on Mercedes.
Rear remains unchanged in some applications.
They just throw larger front sway bar.
Some race BMW don't even run rear sway bar.

Originally Posted by FCobra94

Sure, everyone's experience will very depending on other mods involved, driving conditions, driving style, etc. The post below does a great job of explaining why that's the case (great overall thread in general actually):
http://www.1addicts.com/forums/showp...2&postcount=15

It's obvious that you can't just bolt on a stiffer bar, run some lame staggered tire setup with 225s up front, almost zero static camber, then assume that you'll be king of the auto-x that weekend...I wouldn't expect that of any singular suspension mod; E93 M3 sway bar included.

I see I see

Correct me if I'm wrong but you're saying since a machp strut has negative camber gain only in the beginning of travel then turns positive, the sway will help prevent it from going positive actually increasing grip relative to stock

[bbnks2]

Originally Posted by feuer

Ok flame suit on lol
Rule of thumb for "solving" under steer with sway bars:
Fwd-upgrade rear sway bar
Rwd-upgrade front sway bar
Is about weight transfer.
Why else would m3 e93 have largest front sway bar?
AMG does the same on Mercedes.
Rear remains unchanged in some applications.
They just throw larger front sway bar.
Some race BMW don't even run rear sway bar.

M3 has a larger rear bar as well... tuning swaybars, and suspension in general, is a balance game. There is no one-size-fits-all recommendation. Camber loss causes the outside shoulder of the tire to take a beating, but that is not primarily what causes the front end to lose grip first. The front end loses grip first on our cars because they came off the factory floor with staggered tire setups.

If you leave the insanely soft stock springs in place, then yes, adding a bit more front and rear bar will help reduce body roll and reduce the amount of camber loss up front due to the mcpherson design up front... I can say first hand that the car will feel more planted and more agile on the street.

The actual real world impact on under-steer is negligible though. At the end of the day, the staggered tires is what causes the front end to lose grip first. Adding more front bar stiffens the front end and will cause the car to under-steer more.