Tires for autocross

[yoshi37]

Sounds good, I think I have a laser thermo somewhere in the garage that I'll bring with me next time.

I'll try the camber specs next alignment too. Last time out was my first time with the -2.5 front and I was struggling with oversteer on corner exit. I was still using the ECS02 so I wasn't sure if it was just because of the increased camber or a combo of increased camber with street tires.
My "fix" at the time was just to delay getting on throttle. Do you think I just need to be more patient with throttle or am I doing something else causing the oversteer?

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[NightmareMoon]

What are your swaybars? They're the easiest way to dial understeer / oversteer BUT old street tires (old any tires) will generally increase oversteer, and the car is 400+hp RWD, so oversteer on exit is completely normal. A GT with 3.73s has a ton of torque in 2nd gear. Its part of the drivers job to feed in power as the steering wheel straightens out.

If you can't unwind the steering wheel you can't add power without overwhelming the rear tires, so its mostly technique. If you CAN flat foot while exitting a corner, then you either didn't take the corner fast enough or you're getting on the gas too late. Getting the alignment /swaybars /shocks dialed in will give you more grip on exit, but its still a linear process of straightening the wheel and feeding power progressively.

+ So less oversteer from softer rear swaybar and/or stiffer front swaybar.
+ You can also stiffen the front rebound on the shocks (or soften rear compression).
+ In your case more rear camber should help.
+ Finally, of course getting much better autocross tires than the ECS02 are a huge deal.

 

[yoshi37]

Stock PP1 swaybars, front suspension is stock magneride except for the camber plates. Rear I have the Steeda differential bushing inserts, subframe braces and alignment dowels, FP knuck to toe link bearing assembly and recently put in Cortex rear monoball bearing kit as those OEM bushings were tearing.

Based on your info, I'm guessing my struggle was a mix of old ECS02 tires and improper technique. I have a front/rear dashcam that I plan on rotating the rear to face inwards so I can hopefully film my inputs to see what I'm doing.

 

[yoshi37]

Just to give an update: First weekend on the Vitours were great. Once they were up to temp it, the grip was night and day vs my old ECS02. I ended up settling on 31 psi front and 30 psi rear but I think I can drop it a bit next time.

I finished 4/6 in CAM-C but my X runs at the end were almost a second faster than my best official time. The top guy in CAM-C has a Mach 1 and he rode along for my first X run and gave some pointers. After that is when I saw my times start dropping.

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