zcar_dad

Got front and rear adjustible camber arms for Christmas. My 2007 Z is not lowered. Any suggestions on how much negative camber and toe in to set for autocrossing? Thanks

plumpzz

iTrader: (10)

Try stock first and mod from there? It all depends on your total suspension setup I believe.

AznSky

iTrader: (12)

I'm kind of interested too to see what ppl run as I'll probably be getting suspension sometime this year.

terrasmak

iTrader: (8)

1.5 to 2 front and 2 rear. I would wait to install for when you get your suspension

zcar_dad

I have Hotchkiss sway bars with adjustible end links and Stillan chassis braces. Don't want to do coilovers just yet.

julian

put more negative in the front than the rear. -2.5 front, -1.5 rear. 0 toe in front. 0 or slight toe in in rear

Peak350

iTrader: (6)

You probably like a looser car (I do as well).

I have ~2.7 front, 2.0 rear, and am very happy with how it drives. With 2.2 front it doesn't feel like enough, with 3.2 it feels like too much.

ldstang50

iTrader: (2)

What it ultimately comes down in tires. A grippier tire will cause more body thus meaning you need more negative camber. Size tire is also something to consider as with roll stiffness. Hotchkiss bars will help with roll, but you still have stock springs/shocks. If you auto-x, the control arms (I believe) will put you in SSM

guitarist

iTrader: (1)

I'm pretty sure the 2009 rules allow control arms in BSP. But without a very expensive build up (like Peter Umino's old car) you're not going to be competitive in BSP either.

As for the OP's original question: I'd start at 2.0 negative camber in the front and 1.5 in the back and go from there based on tire temps, tire wear, and handling attributes. Test'n'tune, test'n'tune until the budget is gone or the setup is right.

Z1NONLY

iTrader: (2)

My car ended up with -1.6 front and -2.2 rear, 1/8" toe out front and 1/8" toe in rear. (after my RSR Ti2000 springs)

I "run what I brung" at the track, but my car spends most of its time in the garage, so I wouldn't call it a DD.

That being said the weekend fun drives / occasional road trips / lots of autoX results in close-to-even tire wear.

The rear could use just a little less -camber though.

That's just a tire wear perspective though. I think another 1/2 degree of neg camber up front might make her a little faster, but I have yet to test that theory. (Too cheap/ lazy for A-arms.)

Peak350

iTrader: (6)

You can run control arms in BSP, and I think there is a street tire class pending for the Z (was talking about it yesterday with a local S2000 guy who runs regionals/nationals) so that could be fun.

Camber arms are allowed, however, only uppers, and you can't go with the SPL arms (legally, locally the guys I'm running said they don't care, they'll beat me regardless, but I still asked) because of the bushing material rules. You can't go to a different ratio of bushing material to metal than factory, which means for good arms, cusco more or less.


Edit, and to follow up, I still have understeer with -2.7 degrees of camber front, I set my front shocks stiffer to keep roll down, and stiffened the rear a ton and it helped, but I still think (looking at tire wear and handling characteristics, had no pyrometer) I might move to 3.2 for the next event.

Car could use sway bars though.

ldstang50

iTrader: (2)

Thats good to know. I might do that for next season.
The z is excluded from the street tire class. The only z that is close to eligible is the vert. But the engine size is too large. Yet again, the z gets screwed.

http://scca.com/newsarticle.aspx?hub=3&news=3629

scotts300

iTrader: (46)

I can't believe you have all that camber nonsense with stock sway bars!

Peak350

iTrader: (6)

The transitional stability and roll was pretty well controlled. Shocks-springs-alignment- then sways. It's the way I was taught to set up a car.

PDX_Racer

iTrader: (2)

Don't be too certain about that restriction. There are other cars on the list of "allowed" cars that are faster in stock form than the Z.

guitarist

iTrader: (1)

It seems pretty clear that they've ruled out the Z:

- Engine displacements up to 2.8-liters

Unless you're saying they will change the rules to let it in at some point in future. But that seems unlikely given the cars already in the class.

Peak350

iTrader: (6)

They should look into it. Local clubs have very popular street tire classes. A club I've been running with has a street mod street tire class that gets 1/3 of the days entries.

guitman32

iTrader: (15)

Yea it sounds like you need a rear bar to dial out that understeer. I would try dialing down the front shock stiffness also. And all this before paying for another alignment definitely (unless you set your camber yourself )

Peak350

iTrader: (6)

SPL arms use shims. The toe doesn't really get messed with (much) when you adjust, and the shims are measured.

My alignment was done at 3.2, I was thinking that was near 2.5 before I went in.

PDX_Racer

iTrader: (2)

Why not? The S2000 is classed far faster than the Miata,