The Official 370Z Autocross Thread

[Ruff]

Originally Posted by ChrisSlicks

I installed the Hotchkis sway bars, full set. The car was dramatically better in transitions, however it made the low and mid speed understeer much worse. I can only imagine that it would be worse still without the rear bar. I corrected the understeer by adding front camber using the SPC replacement upper arms. I'm going to build the car up for BSP as I want to focus on track as much as Auto-X.

What size tires were you running front and rear?

The reason I say go square is will help with the low speed understeer, even with the bigger front bar.

For stock class, I really don't think the car can get it done without shocks. But regardless, run a big front bar and a square tire setup.

[ChrisSlicks]

Originally Posted by Ruff

What size tires were you running front and rear?

The reason I say go square is will help with the low speed understeer, even with the bigger front bar.

For stock class, I really don't think the car can get it done without shocks. But regardless, run a big front bar and a square tire setup.

I'm running 275 front 305 rear. Didn't really want the 305 rear but it was the best fit diameter wise. I think the front is pretty much maxed out for the stock size rims. Hoosiers would help but I think you'll be cording them pretty quickly with the stock alignment.

The stock shocks actually seem to work pretty well in conjunction with the uprated sway bars, although probably not quite as well in stock class as you are stuck with the stock rear sway bar.

[Ruff]

Originally Posted by ChrisSlicks

I'm running 275 front 305 rear. Didn't really want the 305 rear but it was the best fit diameter wise. I think the front is pretty much maxed out for the stock size rims. Hoosiers would help but I think you'll be cording them pretty quickly with the stock alignment.

The stock shocks actually seem to work pretty well in conjunction with the uprated sway bars, although probably not quite as well in stock class as you are stuck with the stock rear sway bar.

That's your problem right there with the low speed understeer. And no way in hell are you maxed out on 275s on stock wheels, we run 295 hoosiers on the stock 18x8 350z wheels with no problems, and by far the quickest setup with the car being super neutral. Unless you are talking street tires that are dual purpose. Then you're on your own and the car will kinda suck at autoxing. Until you got to a square setup, you'll going to have tons of understeer auto-xing a Z. And with that much rubber up front, even with stock alignements, they last quiet a while.

[pgrmstr]

So any news on the shock development front?

I emailed Lee@koni but have not heard back from him about any progress. I also email Vorshlag concerning the possible AST strut...and Terry is needing a pair of stock fronts for measurements....so it doens't sound like much movement there. I have thought about pulling my fronts off and shipping them to him as my car is stored for the winter...but I need to call him and discuss what the plan is with AST....SA or DA and what kind of cost. I'm not wanting to spend $2k+ for a SA...but if its a DA, then I would likely pull the trigger.

The other thought I had was going with the Nismo struts. I know they aren't adjustable, and not sure if they'd be legal....I assume the ride height difference is done with the spring, not the strut....but assuming they are legal, and you can find a inexpensive take off set....do you think they'd be worth do the job for the 370?

[ChrisSlicks]

Originally Posted by pgrmstr

The other thought I had was going with the Nismo struts. I know they aren't adjustable, and not sure if they'd be legal....I assume the ride height difference is done with the spring, not the strut....but assuming they are legal, and you can find a inexpensive take off set....do you think they'd be worth do the job for the 370?

The Nismo spring is only about 10% stiffer, but the strut has about 80% more damping so yes I would say it would be a big improvement. I can't see any reason why it wouldn't be 100% legal, you can pretty much run any stock type dampers you want.

[AutoX Z]

Originally Posted by ChrisSlicks

The Nismo spring is only about 10% stiffer, but the strut has about 80% more damping so yes I would say it would be a big improvement. I can't see any reason why it wouldn't be 100% legal, you can pretty much run any stock type dampers you want.

The issue would be the spring perch location. If the nismo is lowered by some combination of changing spring perch height then the nismo struts would not be legal.

[pgrmstr]

IIRC correctly, the front struts are about 40% increase in rebound, and the rear is like 140% or something close....so are much stiffer, but as Autox Z states, its all about the spring perch right hide question on whether is legal...

Obviously the tun-ability of an adjustable shock is preferred, but looking for inexpensive alternatives should legal adjustable units not be ready for the season....and perhaps a Nizmo take off strut would offer an interim improvement for us...