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Discussion Starter #1 (Edited)
I took my 88 GT out to my local track for Sat. night grudge. Overall the car performed well but I expected my 60's to be better. The car goes straight and gets decent weight transfer but it just won't stick. It will spin as soon as my boost starts kicking in. It will also spin in second a little. The car is a 5 speed so i'm just holding the tach at around 3600-4000 then dumping the clutch. I was trying to find a sweet spot with no luck. Heres a rundown of my set-up

Front: lakewood 70/30's with 14x125 coilovers
PA Racing K-member
Removed front sway bar
Skinnies up front

Rear: Removed sway bar
Removed Quad shocks
strange 10 way adjustables
stock gt springs
Baseline suspension stage #2 adjustable upper control arm kit
Baseline Anti-Roll bar
Maximum Motorsports xtreme duty weight jacker style lowers
3.55's with 31 spline and Detroit tru-trac
26x11.5x15 ET Streets

The engine is a built 306 with an S-Trim. I have the pinion angle set at 1 degree per Kevins instructions. Heres what my ET's and 60's were last night..

[email protected] 1.62 60
[email protected] 1.61 60
[email protected] 1.62 60
[email protected] 1.59 60

I'm trying between 10.5-11.5 psi in the rear tires. I tried changing the setting on my strange 10 ways in the rear from soft to firm, with a setting of 7 netting me the 1.59. I honestly think my tires have alot to do with it. They have alot of runs on them and are around 2 yrs old. I'm looking at picking up either MT ET Drags or Hoosier slicks 26x10x15. Any suggestions are welcome :salute:
 

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What pressure did you have the rear tires at? Sounds like you didn't have them low enough. I'm assuming that pinion angle is minus 1 degree, not positive 1 degree.

Tires should be around 12.5 psi cold before the burnout and 14-15 psi afterwards. If you have rim screws, you can take them down to 10.5-11 psi cold and 13 psi hot.

Also, those 125 lb coil-over springs might be a little too weak for your setup, not giving you enough lift. I'm running 135 lbs springs up front with a carbed setup with a lot of weight stripped off the front, ie only accessory is the alt and tensioner, no front bumper, no sway bar, no smog, no EFI crap, etc... They are a little soft IMO, but seem to be working OK for my car.
 

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Discussion Starter #3
I was playing with my tire pressure. It was between 10.5-11.5 cold. Yes I have 1 dgree negative on the pinion angle. I hope its not the springs because I just installed them. I was running some 12x225 springs before. The car is getting good lift up front and holding it, but the tires still spin. It sure doesn't seem to be the springs. What do you think about my 70/30's? I wonder if I need some 90/10's or some adjustables. What should optimum ride height be at the track? Should I have it slightly lifted or lowered down a bit?
 

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Do you have a video? Thats the best way to see what the car is doing. But I think I'd switch struts. Sounds like the nose isn't lifting enough with those 70/30's. Adjustables are better than your 70/30's or even 90/10's. You want the rear shocks to be stiff. Softing the rear will make it squat and that unloads (aka spinning) on the tires.

I too had a traction problem when I was on 3yrd old slicks. Plenty of tire left but they were old and started to harden. Slicks do have a shelf life IMO. -Mark
 

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save the ones you have on it for the street and get some et drags, you will see at least 1-2 tenths difference. been there done that, good luck, allen
 

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Discussion Starter #6
Yeah I might have to get some 90/10's or adjustables for the front. I agree with the shelf life of the tires, they're 2 1/2 years old. I'm definitely going with some ET drags next time out. I'm also going to order some 15x8 wheels so I can get a better contact patch on the ground, I was using 15x7 10 hole wheels.
 
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