Iv_z28

Here is the problem:
last time ,in the heat, the car was just chirping, but now, when I shift into second, it jerks and goes sideway, which is not a very pleasant thing... I have street tires [bridgestones potenza's RE730], I tried 28psi and 26psi, 60' was 2.1-2.2, launching at <2k and actually bogging a bit...

Could that be just tires, or possibly bad alignment [I had tire rotated since the last time?] - or do I really need some suspension upgrades - panhard bar , SFC's?? [currently suspension is completely stock]

thank you for your thoughts

Classic

iTrader: (3)

I was in the same situation the last time I ran at the track. I only have stock Firehawks. Basically I was going sideways on the 1-2 shift as well. What I found was that on the street tires (I don't know anything about drag radials or slicks) - if I was at 26psi I would go sideways shifting exactly the same as with the tires at say 30 psi. I am certainly no expert on this, but from what I've been reading, I believe this happens because stock tires do not flatten out when you let the air out beyond a certain point. At that point they start to cup so you are actually decreasing your contact patch. I find I run the best times with around 28-30 pounds in the tires.

Hope that helps a little.

Iv_z28

Yeah, I firuged the same thing about street tires pressure, but my last run was at 28psi. I'd like to figure out if realignment could help or may be something like a panhard bar and SFC's could take care of the problem...
...DR's - yeah, if that's the only option... but I want good cornering on the street and I'm lazy to switch them back and forth all the time.. ..I'd like to think that my car is a 100% street vehicle and doesn't need any special "track preparation"..

Iv_z28

BTW, does anybody know if wider street tires (say, 275/40/17 from SS) allow better launch traction, compared to z28 street tires (245/50/16)?