I know the topic has been touched on in random conversations, but I wanted to hear what your experiences were with our S.

I wanted to know how much wider I need to push out the track of the S before I feel a difference. OR how much of a width-change needs to be made (either in or out) before the vehicle handles differently.

Thanks everyone

 

Will I have to widen the track by at least 20mm before I see a discernible improvement?

 

Autocross? Track?

 

Road racing environments.

 

Depends on how sensitive you are as a driver and how good you are at maintaining the limit.

I think it will have more of an effect on steering feel. I've run +48, +55 and +65 and can tell the difference between all of them in the feel through the steering wheel more than the limit capabilities and performance difference.

 

^ care to elaborate? what differences in feel were perceivable to you when you changed to a lower offset setup?

 

i tossed a set of 17x9 +35s from my VR4 onto the s2k once just for kicks and the handling difference was insane. The turn in and transient response was so crazy that my passenger was complaining about his kidneys getting rocked.

 

Suspension has it, the biggest difference in feel *by far* will be the change in scrub radius.

With a wider track, you increase the cornering speed at which you will begin to lose grip on the outside wheels. But the relationship isn't linear, the theoretical increase in cornering speed will be on the order of the square root of the increase in track width (cornering g's = V^2/r).

Decrease offset by 20mm at all four corners icreases track width by a factor of only ~1.025 (+2.5%). Theoretical increase in cornering speed should be on the order of sqrt(1.025) = 1.012, barely more than 1%.

 

Now my brain hurts.

 

That formula says nothing about track width. R is the distance from the turn center to the centroid of the turning object. Is this case the position of the centroid doesn't change with different offsets. Track width changes the amount of leverage the centroid has on the wheels. Torque is linear of course.

The other factor that could influence how the car feels after an offset change is suspension geometry. Since the lever length changed each wheel will experience a different amount of force as before. Susp geometry is not linear and most likely makes up most of the difference people feel.

I think this topic is too complex for anyone to provide any guiding ratios as to the effect of track width change. In isolation track width change should have a very minor effect, but that doesn't have to be true for the entire system.

Disclaimer: I track but have never even owned an aftermarket set of wheels