Sway Bar Configurations for track

[derbo]

Yea with an open diff a rear bar would be quite intrusive

I just installed the 30mm sway bar with it on the medium setting. I think the setup is a little bit much for the street. I test drove the car on the local mountain road , King's Mountain Road. I noticed on 10mph hairpins, the car understeered like a pig. I also realized my XP12s are terrible for the street as they can never get warm enough..and the dunlops felt like they never were warm enough.

I will leave the setup like this for now and test it at the track and see how it performs.

[M0nk3y]

Do you have any temps for the Dunlops? They do not need much heat.

As far as the bar, 10 mph you're going to understeer regardless.

For example, from the data this weekend I had a 30 mph turn. The car pushed like a pig, but that is just the BMW way.

At higher speeds you should see a difference

[derbo]

Do you have any temps for the Dunlops? They do not need much heat.

As far as the bar, 10 mph you're going to understeer regardless.

For example, from the data this weekend I had a 30 mph turn. The car pushed like a pig, but that is just the BMW way.

At higher speeds you should see a difference

That's what I figured. I don't have temps on the dunlop but it definitely felt slippery up there. It might have been slippery conditions as well.

I hope I will see a good difference at the track.

[M0nk3y]

That's what I figured. I don't have temps on the dunlop but it definitely felt slippery up there. It might have been slippery conditions as well.

I hope I will see a good difference at the track.

Is this your first time out on the tires?

They have quite a bit of mold release that needs to come off. They need at least 2 full heat cycles to be their quickest

[derbo]

Is this your first time out on the tires?

They have quite a bit of mold release that needs to come off. They need at least 2 full heat cycles to be their quickest

They have been heatcycled at 3 track events already. They should feel grippy...lol

[M0nk3y]

They have been heatcycled at 3 track events already. They should feel grippy...lol

Interesting.

I'm going to chalk it up to either them not getting to temp or the surface conditions

[derbo]

Interesting.

I'm going to chalk it up to either them not getting to temp or the surface conditions

Yea I'm thinking because the road is mainly in the shade because of trees and relatively low speed, the tires did not get enough temperature in them. Also the road conditions weren't 100% clean so it was very ideal conditions. That road is not heavily traveled by the public so surface conditions could be the main culprit. I will continue to drive it on the medium setting to get a feel for it.

[rkneeshaw]

Bumping this primarily to revive the conversation.

Stock ZHP sway bar sizes are 23.5mm front and 18mm rear
Stock M3 say bar sizes are 26mm front, 21.5mm rear
M3 CSL sway bar sizes are 30.8mm front, 22.5mm rear
Most aftermarket non-m sway bars sets are 27mm front, 21mm rear
Most aftermarket M3 sway bar sets are 30mm front, 25mm rear

Until now a lot of the conversation has been around recommending a sway bar setup for someone with custom spring rates and lots of camber.

To create the most balanced car (or at least cut down on understeer as much as possible), what sway bar setup would you recommend for:
1. Stock ZHP suspension and stock alignment specs (I believe -1.5 camber front and -2 camber rear)
2. Stock ZHP suspension and aggressive alignment specs (-3 camber front, -2 camber rear)

Sounds like most are recommending a stiffer front bar, but leave the rear bar stock?
In my previous life with a FWD car, everyone wanted a larger rear bar to increase oversteer/reduce understeer, but that doesnt seem to be what everyone wants to do in our ZHP world?

And, what to make of this on Turners website:

We put together this special sway bar set for the SpecE46 racing class (SE46) and any other E46 that gets heavy track time. We use the 30mm M3 front bar combined with the 21mm E46 non-M rear bar. From our time racing the E46 in World Challenge, Grand-Am, and SCCA club racing we found that the E46 likes a stiffer sway bar and less spring rate. Taking the M3 front bar, which is solid, is exactly what we wanted. They are adjustable in the front (3-position) and the rear (2-position) to fine tune the handling. Bushings are included and new adjustable links are optional. These bars are crafted from a special spring steel that is both stronger and more resilient than competitive sway bars. They have been shot peened and heat treated, and feature precision forged ends.

Setup: The bars are adjustable so any driver can find an ideal setup for the type of driving they are doing. The sway bar becomes stiffer in the holes furthest from the end of the bar. The holes at the very end of the bar are the softest setting. We would generally recommend starting out with the front bar set to the stiffer setting and the rear bar positioned in the soft setting. Adjust to your liking from there.

[rkneeshaw]

To create the most balanced car (or at least cut down on understeer as much as possible), what sway bar setup would you recommend for:
1. Stock ZHP suspension and stock alignment specs (I believe -1.5 camber front and -2 camber rear)
2. Stock ZHP suspension and aggressive alignment specs (-3 camber front, -2 camber rear)

Anyone have any thoughts on this?

I'm tempted to pick up a M3 front sway and try it out. I'm due to replace my sway bar links and bushings, but dont want to buy new rear bushings if I'm going to end up going with a larger rear bar too.... not sure what to do??

[slater]

good bump. i was reading about this a few months ago and picked up a used M3 front bar for $45 shipped on ebay! have not installed it yet, but i picked up some poly bushings for it and some poly bushings for the stock rear bar. going to try out that setup with my bilstein PSS (also not yet installed...) and see how it goes...

peter