The Official 370Z Autocross Thread

[ChrisSlicks]

Originally Posted by pgrmstr

I don't see any slip light, or at least I don't notice, but I know the car is not applying any brake to that spinning wheel.....I assume your VDC is OFF when running?

Yes my VDC is off, but even with VDC off traction control can kick in if it sees a lot of wheel spin at the rear wheels. I only see it kick in if I get inside wheel spin, if both wheels spin then it doesn't kick in. Perhaps your stock VSLD is toasted and has turned into a peg leg? A few of the track guys have reported killing theirs. Mine still works but I haven't had any co-drivers.

[pgrmstr]

Originally Posted by ChrisSlicks

Yes my VDC is off, but even with VDC off traction control can kick in if it sees a lot of wheel spin at the rear wheels. I only see it kick in if I get inside wheel spin, if both wheels spin then it doesn't kick in. Perhaps your stock VSLD is toasted and has turned into a peg leg? A few of the track guys have reported killing theirs. Mine still works but I haven't had any co-drivers.

Hmmmm.....perhaps I am staying under the "lots" of wheelspin threshold...as in the difference of rotation from one side to the other. If I get it, I will ease off slightly...but I can keep that 10% slip for quite awhile so I know the brakes aren't kicking in.

my LSD is fine, as I can induce both wheels to spin and drift the rear at will...my car only has 6,000 miles.....and only 4 auto events on it with a single driver

[ChrisSlicks]

Originally Posted by pgrmstr

Hmmmm.....perhaps I am staying under the "lots" of wheelspin threshold...as in the difference of rotation from one side to the other. If I get it, I will ease off slightly...but I can keep that 10% slip for quite awhile so I know the brakes aren't kicking in.

my LSD is fine, as I can induce both wheels to spin and drift the rear at will...my car only has 6,000 miles.....and only 4 auto events on it with a single driver

Sounds like your diff is okay then. My car also only has 6000 miles but closer to 20 events and so far seems to be holding up.

I only see the wheel slip light in certain corners that lighten the rear wheel, but it was definitely easy to reproduce on race tires especially on the first run. After the tires had some temperature it didn't seem to be as frequent.

[Ruff]

Originally Posted by pgrmstr

yeah, I noticed that......course dependent situation? Or are those guys that fast? Having run both the 350z and the GXP, how do the two compare on course?

They are THAT GOOD. I drove the wheels off the 350z last year and I wasn't even that close to Heitkotter last year at Nats. Given that the 370z is probably far superior to the 350z, I still think the car has a huge chance though. Without having driven it, I can't comment on to wether or not I feel it could be an overdog.

So the GXP vs Z comparo: The GXP feels nearly as quick as the Z, except the Z has much longer legs and I have to shift to third on nearly any autox course (we shift to third around 52 mph, top of 2nd isn't much higher, and the car makes way more power shifting to third rather then hitting redline in second). But other then that, the GXP can nearly hang with the Z in acceleration, due to its short gearing (which is also its downfall as stated before). Now in terms of handling, it's omg, this thing is ridiculously amazing compared to the Z. First off, the GXP has fully adjustable suspension along a wide range of adjustments. (factory camber, caster, and toe adjustable). We have the front at 3 degrees negative camber iirc, turn in is crisp, steady state cornering is on par with the Z (this is the Z's strong point, put me in a sweeper in the Z and I could kill most stock cars) and the ability to get on the throttle is slightly better then the Z's. Where it really kills the 350z is initial turn in, and in quick transitions and slaloms. The Z really shows its weakness when you need to quickly change direction, etc. It's due to it not having enough negative camber, and its slightly long wheelbase. Lastly it being slightly heavier then the GXP (2960 on the scales at Wendover iirc). And lastly, the stock diff in the GXP is amazing, where as the Z is ho-hum. They aren't on the same level in terms of autox, hence the reason the Z is classed lower. No doubt in my mind, I am way faster in the Solstice.

Originally Posted by ChrisSlicks

Yes my VDC is off, but even with VDC off traction control can kick in if it sees a lot of wheel spin at the rear wheels. I only see it kick in if I get inside wheel spin, if both wheels spin then it doesn't kick in. Perhaps your stock VSLD is toasted and has turned into a peg leg? A few of the track guys have reported killing theirs. Mine still works but I haven't had any co-drivers.

You must not be disabling it all the way, cuz every 350z I've driven that was VDC equipped, you could completely disable the VDC and TCS.

[AutoX Z]

Originally Posted by ChrisSlicks

Yes my VDC is off, but even with VDC off traction control can kick in if it sees a lot of wheel spin at the rear wheels. I only see it kick in if I get inside wheel spin, if both wheels spin then it doesn't kick in. Perhaps your stock VSLD is toasted and has turned into a peg leg? A few of the track guys have reported killing theirs. Mine still works but I haven't had any co-drivers.

That's the "electronic" diff kicking in. Even with the vdc disabled this program keeps running and helps the crappy diff by applying brakes to spinning shells when the diff can't keep up.

[ChrisSlicks]

Originally Posted by Ruff

You must not be disabling it all the way, cuz every 350z I've driven that was VDC equipped, you could completely disable the VDC and TCS.

Originally Posted by AutoX Z

That's the "electronic" diff kicking in. Even with the vdc disabled this program keeps running and helps the crappy diff by applying brakes to spinning shells when the diff can't keep up.

Yep. Can't kill it completely without disabling the Bosch module under the center console.