[vasillalov]

Hi Everyone,

I am doing some research on rear sway bars for my E90 track car. My car is FBO, caged, gutted with OSGiken LSD and full M3 linkages. I run TCKLine single adjustable coilovers, solid bushings for everything.

I am looking to reduce the understeer that is still present even with the multitude of modifications that are listed above.

So, in doing research I discovered that there are several interesting options for rear sway bars depending on the diameter of the bar. Here is what I've found so far:

OEM:

335i Sedan RSB: 33556764425 D=13MM
335i Vert MSport RSB: 33556764427 D=15MM

M3 Vert RSB: 33552283962 D=23,6MM
M3 Sedan RSB: 33552283655 D=22.5MM
1M Coupe: 33557845522 D=22.5MM

Aftermarket:

CobbTuning RSB: D=15MM
Dinan RSB: D=15.8MM
ECSTuning: D=15MM
H&R RSB: D=20MM


Looks like the Stock 335i RSB is 13MM in diameter which is the smallest and the M3 Convertible RSB is 23.6MM in diameter which is the largest.

Considering that I have full mods + an awesome LSD, I would be looking for something closer to the M3 RSB.


Questions:

1) What's the difference between M3 and 1MCoupe sway bars? Which one fits my car? I know the 1MCoupe is narrower, but it has the same subframe as M3. Also, I know the M3 has a wider track and different geometry than 335i. So, do I get the M3 RSB or the 1MCoupe RSB?

2) Is the M3 Convertible RSB an overkill and create too much oversteer?

3) Is there anyone running H&R RSB on a dedicated track car? What are your impressions?