Track street car, Ohlin DFV's with standard supplied springs, 2000 model with stock sway bars.
6.0 caster, 2.5 neg front, 2.0 neg rear, zero front toe
No aero other than factory stock front and rear
Running staggered wheel tire with BFG RS1
What rear toe would you suggest for the rear.
I have had suggested 3/16 - 1/4 max toe in, sounds like a little goes a long way.
Track day car driven to events.
Suggestions needed! And yes I have looked!
Thanks

 

The Ohlin DFVs look to have 100N/mm front and 80N/mm rear which has already shifted the handling balance from the stock spin-happy AP1 to some level of less spin-happy. Many AP1 guys like 3/16" toe-in at the rear and more negative camber. I'd try even negative camber front and rear, so -2.5 and the 3/16" toe-in. From there, see how you like it and adjust toe-in at the rear as necessary.

 

To me, 3/16" total rear toe (0.43 degrees) is a lot. I tried a lot of rear toe (1/4"), and for me it sucked pretty bad. More wandering around over undulations and in wet conditions, more understeer mid-corner, WAY more tire wear. I knocked it down because my rear tires were GONE after 4 track days (which did no help stability at all!). Asked the shop for 1/16" per side and they instead gave me 1/16" total. I was concerned that the car was going to become unstable based on suggested settings found here on s2ki, but lo and behold it handled GREAT. And rear tire life doubled.

Every car I've tracked a fair amount (240Z, S2000, FD) has loved near-zero rear toe, and pretty much hated anything more than ~1/8" total. I run 0.2 degrees total rear toe in on my AP1 (0.043" per side, 0.087" total).

This is partly a personal preference thing, but to me it only makes sense to run as little toe as possible in terms of maximizing grip by not having left and right-side tires oppose each other and in terms of maximizing tire life. Particularly for tires that generate a lot of grip per slip angle.

 

This. .1 deg per side and .2 deg total toe in.

 

I think 1/16" might be the ideal, but I wanted to err on the side of caution, i.e. understeer. I'm AP2 which is inherently a little more stable, square tire setup, 20% stiffer front spring rate than rear, stiffer front bar, no rear bar, and 1/16" total toe-in at the rear, even camber front and rear.

With his setup still being on staggered tires and stock sway bar setup, that sorta offsets my square tire setup and stiffer front/no rear bar setup. Granted, the Ohlins is actually 25% stiffer up front....

3/16" will be a safe setup that will probably understeer a bit. If comfortable, can change to 1/16".

 

Thanks for the suggestions!

I was going the wrong direction as in toward zero and it was not suited to my driving style and or set up.
Adjusted to .15 to split the difference and it is amazing how such a minute change can effect the handling so much!
DE this weekend and I will report the final findings.

 

Considering your setup, I'd go with stock 0.15 degrees on each side or go up to 0.20 on each side depending on how you like the balance. 0.15 degrees each side is a good starting point.

 

I run 1/16" total in the rear and really like the setup. Ive got a big front sway though.

 

I had it adjusted to .15 and it made a big difference. The car was much more predictable, no drama!

So I am going to put some of the camber back in the front and rear and push the rear toe back in just a fudge more to pickup some of the grip I lost.

Thanks for the help guys!

 

Is the toe adjustable front and rear?