track wheels and tires

[The Radium King]

thanks folks. I am building a nasa st-3 car to race with the regional association up here (a modified version of nasa pending full adoption) 20 minute sprints. I am allowed dot tires to 275 (to keep the weight and hp reasonable, anyway). I was trying to keep the initial entry cost down and run on the 17" for the first season (fire suits, transponders, fire suppression; all adds up quickly) but am finding tire sizing limited. I may put the 17's on my street car and move the 18s onto the race car.

regardless, good to know that a 235 works on the 7" front - balance is good with a 235/255 combo?

also, I've read good things about the bf Goodrich r1-s compared to the hoosier r7 - any experience with these?

thanks.

[Topless]

Originally Posted by The Radium King

thanks folks. I am building a nasa st-3 car to race with the regional association up here (a modified version of nasa pending full adoption) 20 minute sprints. I am allowed dot tires to 275 (to keep the weight and hp reasonable, anyway). I was trying to keep the initial entry cost down and run on the 17" for the first season (fire suits, transponders, fire suppression; all adds up quickly) but am finding tire sizing limited. I may put the 17's on my street car and move the 18s onto the race car.

regardless, good to know that a 235 works on the 7" front - balance is good with a 235/255 combo?
also, I've read good things about the bf Goodrich r1-s compared to the hoosier r7 - any experience with these?

thanks.

235/255- Yes, a slight sway adjustment may be warranted to fine-tune car balance

R1- Good grip, last longer, not quite as fast as prime HC R7s. (1 sec/lap??)

[thstone]

Originally Posted by The Radium King

regardless, good to know that a 235 works on the 7" front - balance is good with a 235/255 combo?

Yes, the wider front tire trims out some of the stock understeer for more balanced handling. Fine tune with adj sways and tire pressures.