What size ET Streets are you talking about? I've ran both ET Streets and ET Drags and there's not alot of difference. If any, the ET Drags heat up alittle quicker. Air pressure has alot to do with what rim size you are running. All slick manufacturers recommend no more than 1" difference between tire width and rim width, but I do know for a fact that 12" rims with 10"or 10.5" slicks equals better traction and stability. All the guys in the 10.5 classes are going in that direction. Steve Grebeck has been well over 200 mph in his Pro 5.0 Mustang on ET Streets if there's any question as to their hook or driveability at high speeds.
I would say to start around 12-15 psi and watch your burn-out patch and your tread. There should be a swirly pattern across the entire tread surface after a few 'correct' burnouts. The rubber you lay down from the burnout should be real close to the tread width of your tires. Video cameras and slow motion replay are 2 great keys to see whats going on under there and also to see what your suspension is doing. And not just from the rear. It will amaze you when you look at the leading edge of a slick under launch and see the rubber wadding up. Ever hear guys say their tires hook good off the line and unload about 3-4 feet out? If you watch, there will be a big roll, about 6" of tire wadding up after launch and as soon as the tire rotates enough to go over that 'lump', it's like running over a big rock...the tire literally jumps off the ground for a split second. Been there, done that. Too little air pressure. Too much air pressure or too narrow of a rim and you're swirly pattern won't go from side to side on your slick. There will be about 1-1.5" on each side of the tread that isn't making contact.
Run as much tire pressure as you can and still maintain a full width print; heat the tires up for no more than about 5 seconds after you see good smoke, probably less; no dry-hops and you should be okay. Anything over 10" slicks on a 4000# plus truck is probably a waste, unless you're talking major hp.
Hope this helps.
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Randy Morrison, SGA Racing. 1987 Ford Ranger-351w. Best ET 11.000 @ 124mph. 2001 NMRA Truck/Lightning World Champion. 2000 FFW TopTruck World Champion. Sponsored by Level 10 Performance Transmissions in Hamburg, NJ. Visit them @
www.levelten.com