hrubago

Setup before: LEDA suspension with 325 front/225 rear springs, front quaife differential, rear adjustable CUSCO swaybar - middle position.

Car behavior: after lift off - tendency to oversteer, after throttle - understeer.

My changes: 285 front springs, car is 2cm higher, central and rear differentials from type R with 35/65 power split.

Which values for alignment now?

Requirements: lift off - the same - middle oversteer, after throttle - middle oversteer. Im afraid of big oversteer like in rear powered cars like BMW M3 :-)

TopBanana

Surely the best thing to do is see how it drives now, then season it to taste?

hrubago

Forgot values before upgrading. And guys in garage asked me for new values ......

TopBanana

These articles are worth a read:

http://www.whiteline.com.au/articles...on_rails_1.pdf
http://www.whiteline.com.au/articles...on_rails_2.pdf
http://www.whiteline.com.au/articles...on_rails_3.pdf
http://www.whiteline.com.au/articles...on_rails_4.pdf
http://www.whiteline.com.au/articles...on_rails_5.pdf

hrubago

Great article. Thx.

911

Hrubago, I spent some time (year or so) sorting the car out (Sti v3) after full mods to my suspension.
I followed the rule that the rear spring rate must be 80% of the front rate, car was transformed after that.
For settings I followed the Whiteline 'Extreme' guidlines, and set maximum caster the MRT top mounts would allow, about 8 deg positive. I think the camber is 2 deg neg all round, can't remember the fr/rr toe in/out just now.
Lowered the car 20mm from stock.

My chassis spec is:

AVO struts/MRT top mounts on front...Whiteline ALK/22mm bars front rear, rear set @ middle hole...2 deg neg camber/8 deg caster. Extended lower rear links, powerflex bushes everywhere...solid rear links

hope this helps. 911

RRH

I run max camber all round on the RA, can't remember exact front caster, but would try rears parallel initially.

hrubago

Thanks. Yesterday I have first testdrive.
Big, big disappoitment............. :-(

Whats the problem?
There is big change in car behavior. Before the car could be oversteered on lift off in the corner. Now - neutral or understeer. (i went on central LSD in 1st green light from open position).

Brake didnt help significantly.
But: with the throttle on - the car looks to be neutral.

Problem could be:
- 2cm higher car
- softer front springs or bad damper setup
- bad alignment

I also could set the rear swaybar to harder position, but I think its not the ideal way. (worked well before).

I have alignment measure (before and now and there are no big differencies).

TopBanana

I would toe out the rear wheels slightly to promote lift off oversteer

RRH

I'd be a bit careful about running toe-out on the rear from experience- the R's and RAs are **** happy enough with parallel, toe out can make them quite lairy

hrubago

I think so that toe out will be the solution.