Re: Set up and balance.

[rsdreamer]

Hi to all.

I'm using my B5 2000 MY S4 avant this year for some sprints.

The car has H&R coilovers and arb's at present, and part worn t1/r's on the front and new t1/r's on the rear. Unfortunately, I just can't dial out the last bit of understear !!!

I need a fraction more turn in, (bite).

Does anybody know if the B5 RS4 front arb is stiffer or looser than the H&R front bar. Can't make the rear any stiffer.

Hope someone knows the answer.

Regards,
rsdreamer

[fletchie55]

I believe the RS4 ARBs are the same as the S4s which are not as thick as the H&R ones.

[rsdreamer]

fletchie, if that's the case, time to put my old S4 front arb back on then.

rsdreamer

[david7m]

Wouldn't putting the good tyres on the front increase grip/reduce understeer? How about tweaking the tyre pressures?

Dave

[rsdreamer]

David, thanks for the comment, but the t1/r's perform better when tread depth, (and therefore tread roll), reduces.

In putting the new tyres on the back, I'm inducing a little overstear, ie, helping to reduce understear.

rsdreamer

[david7m]

Cool, kinda like slick tyres then!

For maximum oversteer, try running 60psi at the back ha ha

Dave

[jfeb]

I believe Doug at MRC produced some adjustable mounts for the ARBs which enabled him to get (the rear ARB at least) even stiffer than the standard "stiff" setting on the thicker H&R ARB. This might help you?

You have the thicker of the two rear H&R ARBs I assume?

[rsdreamer]

jfeb, hi.

I already have adjustable rear arb links, but all they do is position the bar, not stiffen or loosen it. The only way to stiffen the bar is to drill another link bolt position closer to the front of the car, and there isn't really enough flattened end to the arb to do this comfortably.

You are correct, I do have the 21mm bar fitted.

Looks like going back to my standard front bar and giving it a go.

rsdreamer

[DavidT]

The brackets doug made shorten the rear arb arms, effectively making it stiffer.

Have you got the front H&R arb on the hard setting ? if so, change it to soft it will make a big difference to the balance.

I can't follow your logic on tyres, newer ones are softer so offer more grip, plus more tread = more movement in the tread block = more heat = more grip.

The other thing to do is reduce the ride height, this will increase -ve camber at the front and give you more grip in the corners but wear the tyres on the inside edges.

I have the H&R suspension with 21mm rear arb on hard, front is on soft and the balance is very good IMO, if a little too 'lively' at the rear at times, I've really enjoyed driving it.

Hope this helps.