1LE front end sliding..TC problem?

[WHAMMO]

Ok I need input now. The more I think about it, the more I want to know why;

At my 1st/2nd autocross this weekend, I noticed the front end was 'sliding' off the course and doing a weird noise. The TC was in competition mode most of the time. Is this nanny kicking in?? I was overdriving a bit though, I think.

I got a ride in a base C7 with nannies off and it had twice the grip on Michelin PSS on semi wet course. Boy that car is something! My Goodyear arent dead, but they show good wear onthe outside.

Question is: is TC kicking that early when autocrossing for the front end?? Tires/pressure problem or alignment??

[Nick S]

If you were riding on the stock goodyears then likely they were he culprit as they get pretty slick on wet roads. Especially if it was cooler out and wet.

[WHAMMO]

Ok that was my first impression. Its always kinda cold here and when its hot its just humidity.

[Electric]

I autocrossed my 1LE two weeks ago (first time on this car). Temperature was in mid 60s. Original tires with like 2000 miles on them. Traction/Stability control fully off. Grip was terrible, but I only experienced mild understeer and only when I was asking the tires for too much in the tighter turns. In the higher speed slalom, however, it was a little tail happy.

So, I would say understeer/oversteer bias was pretty neutral, although I did experience a tad bit too much of both.

I attribute this to the tires. With my street tires - Michelin A/S 3, the car behaves MUCH better.

[WHAMMO]

Im glad to hear this cause Im going with the same tires!! So is it possible that those Goodyear are good at lapping but not so much for tight autocross course? The circuit was realllyyy tight. No speed, just a bunch of turns and 'S' at low speed. And its always cold here. Sometimes its hot...and rainy LOL

[Synner]

Sounds like understeer. Best times when stock I got with using the throttle do induce some controlled oversteer. What are your alignment specs?

[Nick S]

The stock goodyears really do not make a good autocross tire as they take longer to come up to operating temp. You need a tire that warms up quickly. Many have found the Michelin PSS and I see a lot of people liking the Hancook RS3's for autocross. I have Michelin PSS's on my car and I feel much more confident in knowing what the tires are going to do during autocrossing than I did with the goodyears. Now if I get a chance to do some bigger track stuff I think the Goodyears will be going back on. Or if I do some mid summer autocrossing where the ambient temps are 70°+ then I want to give the stock Goodyear's a try again.

[Dropspeed]

Everything has been covered but to reiterate:

Goodyears are no good in the wet. (like driving on ice)
Goodyears take a while to warm up. (any temp below 60F is dangerous)
Goodyears are great on track when they are warm.

I have had 305/30/19 Hankook RS3 on the car and they warm up almost immediately, but in a 20 minute session on course they get greasy near the end as the temps/pressure climbs fast

Just switched to a 305/35/19 Nitto NT-05 (200 treadwear) and have been very impressed on the street with the initial 150ish miles I have had then on. They also perform better cool than the Goodyear. I do not intend on tracking these tires.

[Norm Peterson]

Originally Posted by WHAMMO

Ok I need input now. The more I think about it, the more I want to know why;

At my 1st/2nd autocross this weekend, I noticed the front end was 'sliding' off the course and doing a weird noise. The TC was in competition mode most of the time. Is this nanny kicking in?? I was overdriving a bit though, I think.

I got a ride in a base C7 with nannies off and it had twice the grip on Michelin PSS on semi wet course. Boy that car is something! My Goodyear arent dead, but they show good wear onthe outside.

Question is: is TC kicking that early when autocrossing for the front end?? Tires/pressure problem or alignment??

I'm betting it was the stability control kicking in enough to guarantee that you were going to get understeer rather than oversteer.

Other things also seem to be adding their own bias toward understeer . . . alignment and possibly inflation pressures (outer shoulder wear) and perhaps tire wear (with respect to semi-wet conditions).

The C7 is an amazingly capable car. Drive one hard if you ever get the chance.

Originally Posted by Electric

I autocrossed my 1LE two weeks ago (first time on this car). Temperature was in mid 60s. Original tires with like 2000 miles on them. Traction/Stability control fully off. Grip was terrible, but I only experienced mild understeer and only when I was asking the tires for too much in the tighter turns. In the higher speed slalom, however, it was a little tail happy.

So, I would say understeer/oversteer bias was pretty neutral, although I did experience a tad bit too much of both.

I attribute this to the tires. With my street tires - Michelin A/S 3, the car behaves MUCH better.

Sounds like the G:2's might be a little too peaky for your driving style, and a more progressive tire that's easier to drive suits you better. No flame/insult intended.


Norm

[SVThis]

The Goodyears just plain and simple suck for autocrossing. I wasted an entire season last year using them. By the time you get enough heat in them you've wasted runs and this was with two drivers. We switched to the Hankooks this season. So far much better. Our times have improved based on comparison of other cars last season. At the first event this year we paxed 5th out of over 100 cars. No where close to that on the Goodyears last season. I would love to try the new Bridgestone RE71R's on 19 inch wheels. I think that will be the hot setup in F street this year.

[Electric]

Originally Posted by SVThis

The Goodyears just plain and simple suck for autocrossing. I wasted an entire season last year using them. By the time you get enough heat in them you've wasted runs and this was with two drivers. We switched to the Hankooks this season. So far much better. Our times have improved based on comparison of other cars last season. At the first event this year we paxed 5th out of over 100 cars. No where close to that on the Goodyears last season. I would love to try the new Bridgestone RE71R's on 19 inch wheels. I think that will be the hot setup in F street this year.

Can't agree with you more, and I thought I would finally be competitive with this car. :( I'm kinda pissed of at all the car magazines claiming how good these tires grip, while in reality, under normal conditions, these tires will be outperformed even by some all-season tires.

Originally Posted by Norm Peterson

Sounds like the G:2's might be a little too peaky for your driving style, and a more progressive tire that's easier to drive suits you better. No flame/insult intended.


Norm

Yes, I did not yet get a chance to experience these tires in their best temperature range, but at 60 degrees, it's definitive not what I prefer.

BTW, Norm, I remember following your advices back on maxima.org In case you remember, I'm DrKlop on that board and I was active between 2005 and 2008.

[Bizaro]

you need hot weather to autocross these tires.

[Norm Peterson]

Originally Posted by Electric

Yes, I did not yet get a chance to experience these tires in their best temperature range, but at 60 degrees, it's definitive not what I prefer.

BTW, Norm, I remember following your advices back on maxima.org In case you remember, I'm DrKlop on that board and I was active between 2005 and 2008.

Apparently the G:2 is much more of a track tire than an autocross tire.


I do remember that username from over at the .org. We still have our 20AE and I still get over on the .org from time to time.


Norm

[WHAMMO]

All this make a lot fo sense; those G2 grip like hell on the streets at higher speed but not at all on a small autocross run.

I'm betting I will improve my times with Michelin Pilot Sport AS3.

Alignment is stock but I ask Justice Pete for some spec; -1 and -.5 rear. Should be better.