I'm kind of fantasizing for when my engine is complete and I get it to the track this summer. I would maybe like to buy slicks for the heck of it. I was thinking, do you need to get the same diameter tire as the normal tire you run? I would assume so because the way my combo is set-up, it all jives really well (at least I think), and the tire height was taken into account as far as powerband and such. Am I thinking right, or does it really matter?

every engine combo that i have built....if the car was set up for a certain size tire then a larger slick killed the 60 ft time and the rpms at the end of the track leading to lower trap speeds......but im talking drastic tire heights to.....like from going to 29.5 or 30 inch slicks when i would normally run a 26.2 or 27 inch tire.......

one case in my adventures of drag racing my street car would run 1.72 60 ft on a normal basic 275 60 15 everyday street tires. and this wasnt comming out of the hole very hard just enough to keep stuck to the track.......but with slicks 29.5 inches and 150 hp nitrous shot off the line i would only get 1.60's........take the nitrous away and full throttle on the slicks i was only looking at 1.70's again.....

so just think if i was able to come out of the hole with the shorter tire full throttle i'm sure would be able to kick the 60 ft times down a great deal........those bigger tires was sure killing me....specially when i could 60 ft some passes better with street tires over the slicks.......

and the taller slicks sure killed the trap speeds by 2 or 3 mph........and really most passes was slower with slicks over all.....i just used the slicks i had for the nitrous off the line....they was spinning some as you can tell if i was only droping about .10 in the 60 ft times.....oh and ya it was with 4.56 gears too.....

a friend of mine over the summer used slicks on his ride( ya mine 28" MT) which replaced his 255 60 15 tires and he slowed down as well......this car has some torque im telling ya.....with street tires he was running 13.20's at 103 mph with slicks 13.80's at like 98 mph.......besides that he didnt even improve on his 60 ft times....in street tires he was geting 2.15 60 ft times (feathering the gas) and with the slicks full throttle he was spinning them a very honest 15 to 20 feet out of the hole and doing the 60 ft in 2.teens and 2.20's. they came off in a few passes......and on went the street tires......and the car picked up again......

thought i would share.....

Ddennis, what street tires did you get the 1.70 60ft times with and what was your launch technique?