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Question about offset FCAB

3.8K views 9 replies 3 participants last post by  hamonrye  
#1 · (Edited)
I have 225/50/16 tires, if I go with offset, am I in danger of rubbing. I will have Meyle HD control arms and Koni Str.t struts. I have searched and searched, only thing I found that comes close to matching what I am asking were some guys that had 225/50/16 tires rubbing without offset bushings. I do not have any rub currently, and do not want any.
 
#4 ·
Thank you very much. This solidifies my decision (for the time being). I hate spending the money on all this stuff at the moment, but am kind of excited to at least make some changes to the situation instead of in the past where I just tell the mechanic to fix my car with whatever parts they choose.
 
#5 ·
the fcab bushing just increases caster, i thought. :dunno:

unless you put them in wrong....at least that is how they looked to me. i was looking at them, but then decided i do not need any additional caster at the moment.

went with solid meyle mounts. no issues with them.





df
 
#6 ·
the fcab bushing just increases caster, i thought. :dunno:

unless you put them in wrong....at least that is how they looked to me. i was looking at them, but then decided i do not need any additional caster at the moment.

went with solid meyle mounts. no issues with them.

df
The increased caster moves the tire forward, causing rubbing for some people. My question was directed towards, am I subject to be one of those people, if I buy offset bushings?
 
#7 · (Edited)
Again, I installed offset bushings with no other modifications on my car, and I did not rub with the stock sport package wheels with 225/50R16 tires. If you were to use aftermarket wheels, you could rub, but if you're just on stock BMW wheels, you will not rub. Another detail which some people overlook is that if you install the stock sport package wheels on an E36 which didn't come from the factory with the sport package, you may rub at full lock. This is because the tie-rod locking plates on the sport package cars and M3s had an extra spacer on them to keep the wheels from turning to the same angle as the non-sport cars. This is because they came equipped with wider tires, and to prevent those wider tires from rubbing, BMW installed locking plates with spacers. Non-sport cars came with narrower tires, hence they did not need those special spacers.

Anyway, I'll repeat: if you have the stock wheels and have performed no other modifications, you will NOT rub with 225/50R16 tires when using offset bushings. It pushes the wheel forward a little bit, but not much. Here is how much my wheels were pushed forward with only offset bushings installed before I upgraded to a different suspension:

Image


You can see that the front wheels are pushed just a tad to the front, but not very much. It did not rub at all when configured like this. I later upgraded my suspension, and installed the proper M3 upper strut mounts to bring the wheels back to center in doing so, but I never had any issues when I had just the offset bushings alone with no other mods.
 
#8 ·
Did you see any benefits with the offset with stock suspension. I only ask since you have provided a lot of information. I have read many things going both ways on this subject. I just ordered the offset, but since tomorrow is the fourth I can probably change my order. I also didn't see the bit about sport vs non sport. I bought the car used obviously. I have the same wheels as you and have the sport seats and the car came with those sized tires, so I probably have the sport package correct? Ugh. Maybe I need to cancel order and get centered. Thanks for all your help btw.
 
#9 · (Edited)
I think it's pretty safe to assume you have the sport package, but if you want to be 100% certain, there are a number of VIN decoders available online which will tell you what options your car came equipped with from the factory. You just need the last 7 digits of your VIN.

As far as offset vs. centered bushings go, I noticed a massive difference because I went from totally shot non-M rubber bushings to totally solid mount delrin racing bushings with offset geometry. It's hard to really compare the two worlds, since I'm sure I would've noticed a big difference even if I had just replaced my worn out non-M bushings with the same thing. Honestly, for regular street driving I don't think you will notice much (if any) difference in how the car feels from a handling standpoint due to the offset bushing geometry alone. That said, since the offset M3 bushings are nearly solid rubber (unlike the non-M bushings, which have big voids in them to soak up vibrations from road surface irregularities), you will probably notice a difference simply due to the increased stiffness of the bushing material itself.

I upgraded to bushings with M3 offset geometry for a number of reasons, and one of them was that I knew I was going to eventually upgrade the rest of my suspension to full M3 geometry, including the stronger M3 upper strut mounts. If you don't plan on doing that down the road, I probably wouldn't bother with getting offset bushings, and would recommend just getting the centered M3 bushings from the '96-99 M3s instead. That way you will have correct wheel placement, and will still get a handling improvement due to having slightly stiffer control arm bushings compared to the non-M bushings.

Make sense?
 
#10 ·
Looked up my VIN and I have M Sports suspension. So I guess I am safe to keep my order with offset. As far as the future mods I have no idea. In an ideal world I have enough money to get another car and turn this into a long term project. Thanks for your help.