Bigger rear sway bar...

[a3ternus]

So,some months ago I installed a rear sway bar from a 6 cylinder model and now I hate my car! :???:
I mean,the limits are higher but with as much as 120bhp,I think it took all the fun out of the driving experience.The car now is a lot sharper at the limit,
meaning it drifts harder through slow corners but when it does I need to be always on alert just to keep the rear under control.
Maybe bigger is not better in this case,huh?
The car is a M10 1.8lt.
N.

[StereoInstaller1]

In sway bars, bigger in front first, then add enough rear to get happy.

[a3ternus]

In sway bars, bigger in front first, then add enough rear to get happy.

So I should upgrade my front as well?
N.

[shiboujin]

Whats the point of upgrading the sway bar in the first place? but yes, front first then rear.

General rule of thumb:
Stiffer front == understeer
stiffer rear == oversteer

Springs/shocks should be your first line of defense against roll. Sways should aid but not be the main supporter.

[Stu]

I generally like all the rear swaybar I can get using a street suspension. E30's are soft chassis' that flex quite a bit. Camber aside, rear sway bar is one of the best ways to get rotation on turn-in. The way you drive the car has a lot to do with it also.

[a3ternus]

Whats the point of upgrading the sway bar in the first place? but yes, front first then rear.

General rule of thumb:
Stiffer front == understeer
stiffer rear == oversteer

Springs/shocks should be your first line of defense against roll. Sways should aid but not be the main supporter.

Hm,that what I knew,too. :(
Still,what happened ?!?
I upgraded my rear only and since the Alpina headers,
I cant slide the car so easily.Maybe cos I now dont have so much bottom end torque with the headers installed?
I cant understand what happened to be honest! The car is really pulling after the alpina upgrade.
My suspension setup is the classic combination Bilstein/HR.
N.

[87e30]

Whats the point of upgrading the sway bar in the first place? but yes, front first then rear.

General rule of thumb:
Stiffer front == understeer
stiffer rear == oversteer

Springs/shocks should be your first line of defense against roll. Sways should aid but not be the main supporter.

I've read some pretty convincing threads stating that stiffer fronts on the e30 actually REDUCE understeer. For tighter turns I've read it's a good idea to leave the rear sway off for more grip, high speed turns maybe a bit thicker but in general a thick front bar.

[whiltebeitel]

A swaybar just reduces the weight trasfer as the cars rolls in a turn. Up to a certain point, they are beneficial at keeping the roll to a minimum. Too much bar will reduce the independence of the suspension. Less independence means less ability to maintain grip on uneven surfaces (i.e. not a perfectly smooth road course). You can reduce the roll with springs by running very stiff rates, but again, no so great on less-than-baby's-bottom-smooth surfaces.

Generally, more front bar is preferable on RWD cars than rear bar. More rear bar is preferable on FWD cars than front bar.

A nice sway bar rate calculator.

[gearheadE30]

For what it's worth, a big contributor to the need for a large front bar is the camber curve with lowered strut suspension. When the control arms pass the 90 degree point relative to the strut on compression, you are effectively losing camber the more the suspension compresses. A thick front sway reduces understeer, to a point, by allowing the suspension to compress less while turning, which helps with the dynamic camber.

Otherwise, its about the same as any other car, where more body roll causes the tires to lean over more, thus creating positive camber relative to the road.

I have a 21mm front bar and a 14.5mm rear bar. It's great on track, where I could almost use more front bar, but the rear is too stiff at an autocross. That is with 350/475 in/lbs GCs.

[weaksauce]

weak
i fabbed up a mount for a 22mm rear bar for our lemons car.
going to test it next weekend.
I might hate myself for it.....

[Jean]

No rear bar here, can slide it if I want to, but would rather have more rear traction. ..

Worked great at autocross as well, 500front/650rear.

[lifeiskaos]

I have a 19mm H&R rear sway bar installed, but haven't hooked up the links yet. I'm not sure what I'm going to do. I have a 21mm m3 front bar with m3 links, which increase the leverage almost 50%, but I'm still afraid the 19mm might be too much.

I too have heard that stiffer rear bar causes oversteer, and I've also heard that staggered tires causes understeer... Maybe mine will cancel out??

[browntown]

get a cabrio front bar and it should balance out better.

[nando]

Whats the point of upgrading the sway bar in the first place? but yes, front first then rear.

General rule of thumb:
Stiffer front == understeer
stiffer rear == oversteer

Springs/shocks should be your first line of defense against roll. Sways should aid but not be the main supporter.

this is a nice general idea, but not always true. if your suspension is soft enough that body roll significantly reduces camber on the outside wheel, stiffer front roll bars would reduce understeer. coincidentally this is true on many E30s that use soft lowering springs as a performance upgrade..

[lifeiskaos]

get a cabrio front bar and it should balance out better.

Cabrio bars are the same diameter as m3 bars