Does anyone have swaybars?

[AW330i]

I understand the idea behind sway bars and I know that they will increase handling but I would like a guage of by how much. So if anyone here has done sway bars on their e90, not other cars, I would like to know what kind of results you got...

[HRC]

Not sure, but I don't think anyone has released any as of yet. I'm looking at the H&R's. I want to upgrade the rear bar when it becomes available, but not the set.

Danny

[shadye90]

Not sure, but I don't think anyone has released any as of yet. I'm looking at the H&R's. I want to upgrade the rear bar when it becomes available, but not the set.

Danny

Eibach actually has a set available for our cars now...Highly considering a set...

[HRC]

Eibach actually has a set available for our cars now...Highly considering a set...

Oh I forgot about that! Anyhow, can you buy just the front or rear?

Danny

[diesel007]

I have only seen the set.

http://www.bavauto.com/shop.asp

[longtran]

Not sure, but I don't think anyone has released any as of yet. I'm looking at the H&R's. I want to upgrade the rear bar when it becomes available, but not the set.

Danny
why would you only buy the rear?? this is coming from the company that was making the sway bars off my car. i think th front sway bars was 5mm thicker and the rear was 2 mm thicker. as soon as they call me back for the install i will tke some pictures and let you guys know how it goes. maker is uuc motorwerks.

[HRC]

I want to take the understeer out of the car. By upgrading just one, you get that, not so much with the set.

Danny

[longtran]

I want to take the oversteer out of the car. By upgrading just one, you get that, not so much with the set.

Danny
when you get wider tires your oversteer go bye-bye...



Long :bellyroll

[HRC]

when you get wider tires your oversteer go bye-bye...



Long :bellyroll


I meant to say "understeer" lol :bellyroll

Danny

[ksfrogman]

Understeer is a safety feature most car manufacturers opt for.

The SCCA used to allow Solo II participants to add stiffer aftermarket front anti-roll bars in stock class for this reason.

I am very interested in reducing the car's body roll, but noticed that in two previous cars I did this to, the ride seemed slightly stiffer as well, especially over uneven bumpy roads.

[ward]

even with the bars, the car will still understeer, just a bit less than stock

[GoBonesGo]

Understeer is a safety feature...


How so? Not baiting here, I've just never heard that before.

[ward]

How so? Not baiting here, I've just never heard that before.


it's easier for most to recover from the nose pushing wide rather than the tail coming out.

it's not the "fast" way around a corner, but it's the easier to control way for most

[GoBonesGo]

Ah, thanks.

[ksfrogman]

Right. If the nose pushes forward, at least you'll see yourself going off the road in a straight line.

If the rear end comes around and you lose control, your car can do donuts as it skids off the road.

[HRC]

We all know that most cars even the E90 with zsp is designed for the masses. I understand that understeer is a built-in safety feature, and no doubt helps the average driver. I want to fine tune this car to suit my taste, that's all. I guess you can call me an unsafe radical...for decades...

Danny

[ward]

I don't know about unsafe Danny,

I think you just want what we all want, a neutral handling car

for some reason, they won't just give us one right out of the box!

[solo2]

It depends on what you are trying to accomplish and what type of driving you do. Personally, I would look at ways to improve the grip at the front of the car instead of removing grip from the rear - specially on a non-M car where you will limit the ability to put power down when you add the rear swaybar.

Better options:

* Tires with more grip. Yes, the car will grip better all around, but the increase in front-end grip will be more noticable.

* Stiffer front swaybar. I know.. I know.. now hear me out. Part of the reason a car will understeer is that the grip of the front tires is reduced due to body roll. As the car rolls, the camber turns positive and the tires grip much less.

* Stiffer springs. Same reason as a stiffer front swaybar.

I have found the stock E90 to be much better on turn-in than the stock E46.

All of that said, I can't imagine a situation where I would stiffen the rear of the car without stiffening the front. In autocross, I would stiffen the front a lot and add a set of better tires (to start).

Hank
Boston BMWCCA Autocross (Instructor, car-slut, .. )

[HRC]

...I can't imagine a situation where I would stiffen the rear of the car without stiffening the front...

I did this in my last 3 cars and it worked like a charm. All my cars before this has been FWD.

Danny

[ksfrogman]

Here's a good link that discusses the effect of sway bars in weight transfer during a turn, and how this affects under- and oversteer.

http://www.automotivearticles.com/123/printer_Anti-sway_bars.shtml

[lni]

Whose e90 were you making these assumptions on? :D

I have found the stock E90 to be much better on turn-in than the stock E46.

All of that said, I can't imagine a situation where I would stiffen the rear of the car without stiffening the front. In autocross, I would stiffen the front a lot and add a set of better tires (to start).

Hank
Boston BMWCCA Autocross (Instructor, car-slut, .. )

If it was mine, remember I had 255 azenis 615's up front. Trying 275's this season.

[longtran]

Whose e90 were you making these assumptions on? :D


If it was mine, remember I had 255 azenis 615's up front. Trying 275's this season.
275 in front??? :bulge:

[lni]

They fit, but i think there may be rubbing going around cones. I'll try it for a few runs to test it out. :D

In the back, there's probably room for 315's. I may run fatter than 275's later in the season, after these 275's are shot. Even with 275's there's room for a 10-12mm spacer and close to 2" on the back side, to the springs. Once I drop it this weekend, I'll see exactly what I can do for spacers.

[Thavee]

This is interesting. I am about to get a set too. From all's driving experiences, what is the e90 steering nature? Under or Over? (Standard tires and wheels) Let say 325i and 330i not for 320i.
325 and 330 have got heavier engines at the front though.

[HRC]

This is interesting. I am about to get a set too. From all's driving experiences, what is the e90 steering nature? Under or Over? (Standard tires and wheels) Let say 325i and 330i not for 320i.
325 and 330 have got heavier engines at the front though.

Understeer. They all come with understeer engineered in, for safety's sake.

Danny

[lni]

Understeer. They all come with understeer engineered in, for safety's sake.

Danny

I agree, but very slightly. It's more neutral, in my opinion. Sure, any idiot can make a car push, if they are going too fast into a corner. However, it's pretty easy to get the back end around (and control it), with the electronic nannies turned off.

I get a kick out of some of the novice autoxers that I've instructed talking about "man, my car has incredible understeer ". 99% of those people overdrove the car into an element, and paid for it by lack of steering response. I can recall myself making those same comments, years ago.

By the way, if you're understeering, turning in further to the steering lock doesn't help at all. ;)

[ward]

the E90's far less neutral than my Z4

[HRC]

...By the way, if you're understeering, turning in further to the steering lock doesn't help at all. ;)


Yes, you need to scrub some speed and unlock that steering wheel...

Danny

[lni]

the E90's far less neutral than my Z4

I attribute it to being lighter and lhaving ower center of gravity, but the Z4 is a very tossable car, but is similarly predictable, driving at 8/10ths and above.

[solo2]

Larry?? Is that you??

Yours was the only one I had driven. It must be even better now that it has different springs in it!

I forgot to ask during the weekend.. Did you change the shocks too? I wouldn't run the H&R's without changing the shocks.

Hank

[hunter399]

I asked my local bmw shop about intalling the sway bars


They said it would be VERY expensive because of the location of them

[ksfrogman]

I asked my local bmw shop about intalling the sway bars


They said it would be VERY expensive because of the location of themThe front sway bar was very easy to install. The rear one took 3-4 hours and ended up costing me $450 in labor.

[hunter399]

DAMN!
Can you really tell a difference

[ksfrogman]

DAMN!
Can you really tell a difference
The H&R rear bar is so much fatter than the stock one. When only the front one was installed, the car plowed with quick U-turns after braking and quickly accelerating. The addition of the rear bar to complete the set made the biggest difference. Here's the thread with photos:

http://www.e90post.com/forums/showthread.php?t=16273&highlight=SWay+bar

[hunter399]

So with the swaybars and install, it is about 1k.....I ordered the coilovers first and will order the sway bars later

[HRC]

So with the swaybars and install, it is about 1k.....I ordered the coilovers first and will order the sway bars later

Just get the rear bar, that's what I want to do...

Danny

[solo2]

Danny, do you understand that you will be removing grip from the rear of the car this way? Why would you do that instead of adding grip to the front to get rid of understeer?

Hank

[HRC]

I have done the rear bar-only upgrade in all my previous cars with outstanding results, but they were all FWD. Is this not the case with my e90?

Danny


Danny, do you understand that you will be removing grip from the rear of the car this way? Why would you do that instead of adding grip to the front to get rid of understeer?

Hank

[solo2]

A rear bar ONLY change is appropriate with a FWD car, but IMO not with a RWD car. You don't want to take grip away from the drive wheels. You can remove a great deal of the understeer from a BMW by changing alignment and adding some negative camber.

There's a number of variables to consider, but here is the list of changes I would make in priority order:

1. Alignment: The biggest performance mod for the least amount of money. Reduce the front toe to 0 (or just a touch toe out if you don't want the car to follow lines in the road) and rear toe to 1/8" (or less) to reduce understeer.

1. Tires: Adding grip will have the most impact on turn-in and reduce understeer.

2. Camber: Adjustable or fixed camber plates will reduce the positive camber affect during cornering. Take a picture of your car during a right hand turn and look at the front left wheel. As the car leans, the camber goes positive and the tire looses grip. This is a large cause of understeer.

3. Shocks: Adjustable if you can afford it. The stock shocks were not made to handle stiff springs.

4. Springs and/or swaybars: Reduce the body roll! Even with a HUGE front swaybar, I can make the car neutral or slightly oversteer with the right alignment/camber/etc.

Hank

[y789]

Hank;

I am new to this and have some basic questions about your comments. BTW, I have a 325 non-sport.

A rear bar ONLY change is appropriate with a FWD car, but IMO not with a RWD car. You don't want to take grip away from the drive wheels. You can remove a great deal of the understeer from a BMW by changing alignment and adding some negative camber.

There's a number of variables to consider, but here is the list of changes I would make in priority order:

1. Alignment: The biggest performance mod for the least amount of money. Reduce the front toe to 0 (or just a touch toe out if you don't want the car to follow lines in the road) and rear toe to 1/8" (or less) to reduce understeer.

*** is this different from regular wheel alighment? what is a toe?

1. Tires: Adding grip will have the most impact on turn-in and reduce understeer.

*** 159, 17" tires have good size, what are the best tires to consider?

2. Camber: Adjustable or fixed camber plates will reduce the positive camber affect during cornering. Take a picture of your car during a right hand turn and look at the front left wheel. As the car leans, the camber goes positive and the tire looses grip. This is a large cause of understeer.

*** What are cambers? where do I find those?

3. Shocks: Adjustable if you can afford it. The stock shocks were not made to handle stiff springs.

*** I think those are ones offered by the like of H&R

4. Springs and/or swaybars: Reduce the body roll! Even with a HUGE front swaybar, I can make the car neutral or slightly oversteer with the right alignment/camber/etc.


*** do shocks and springs go hand-in-hand when replaces? what swaybars are available and how to decide which is best for you?


Hank

As I said; just basic simple questions ;-)

[ksfrogman]

It's been about a month or so now since I've had the H&R sport springs and sway bar set installed. Unlike other cars I have changed the suspensions on, the 330 ride is quite smooth. I still feel like I'm driving a luxury sedan.

With the springs, the biggest change I appreciate is the sleeker look.

With the sway bars, I notice the biggest difference when I'm driving in my suburban residential tract home neighborhood at 25 mph, and turn a 90 degree turn without stepping on the brakes or slowing down much at all. The car remains almost flat in these turns. Makes the car such a joy to drive around town without even pushing it to the limit.

[HRC]

Yes, I really enjoyed the difference my rear bars have made on all my cars. Like you say, you dont have to be pushing the car at the limits to enjoy the benefits of bar upgrades. I really want one for my car. Flame suit on!:)


Danny