I have been racing my car at the track on Kelly Charger HR 245/50/16 street tires. My car is an 87 IROC 305 TPI with a few mods and a 50HP shot of NOS. Best ET is 13.62 secs @ 102 MPH.

I'm looking to race it again in full street trim but with a 75 shot and a 100 shot of nitrous. Traction is becoming a big issue, even with the 50 shot.

What is the best pressure to run in the rear tires for maximum bite out of the hole? I have been running them at 28 psi.

I am hoping to crack a 12 second pass on street tyres / exhaust / etc.

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1987 Chevy Camaro IROC-Z. 305 TPI. 700R4
14.6 secs @ 93 MPH.
2.14 sixty foot.
Nitrous soon! :-)
http://www.camaro-firebird.org
Camaro and Firebird pages in Sydney, Australia.

 

Find some nice clean concrete and do a mild burnout--don't smoke em' just spin them for a few feet. Check the tire marks. If center is darker than the outside remove some air. If the outside is darker than the center put in some air in. Start around 30 psi


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350 with stealth intake, holley carb, 470 lift cam. 700r4 with .5 boost valve, vette servo, tci lock-up kit, B&M megashifter. Richmond 3.73 gears, powertrax locker, timkin bearings, synthetic lube. Custom 3 inch single into 2 2.5 pipes. 1 1/2 drop springs, 1 5/16 solid front sway bar, 1 inch rear bar, custom subframe connectors, custom LCA relocation brackets. Kobel ground FX, currant red metallic paint. Lots of other stuff...
82camaro

 

Radial tires are not designed to use low air pressure. The center of the tire rolls up when the pressure is low reducing traction. The above mentioned method is best to find out the best pressure. 28 psi is the lowest you should go. Radial tires work best at the track between 28 and 35 psi.

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Follow my racing progress on Stephen's racing page
and check out the race car

87 IROC-Z SuperPro ET Bracket Race Car
461 naturally aspirated Big Block (times are for the current engine)

Best ET on a time slip: 11.447 altitude corrected to 10.99
Best MPH on a time slip: 119.42 altitude corrected to 124.86
Altitude corrected rear wheel HP: 493
Best 60 foot: 1.586

Racing at 3500 feet elevation with a typical race day over 5000 feet density altitude!
Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley