[peterpjb]

Originally Posted by 1795

Thanks for that information. I am trying to figure out which tires to run on my 289 FIA SPF/Riverside Racer. The racing organization that I will run with is specific about tires and sizes. I am going to go with Hoosier Street TD's and the sizes that I am allowed are: 225/60/15, 245/60/15, 275/60/15, 25.5/8.5/15 or 26.5/9.5/15

I am a little concerned about having adequate clearance, and also wanting to make sure that I have adequate rubber on the track. 245 seems way to small for the back, especially given that the 289 will have approximately 450HP at the flywheel.

Any thoughts? I am starting to lean towards 25.5/8.5/15 in the front and 26.5/95/15 in the rear, as they are a little less tall and slightly wider. that will help lower my center of gravity a little and increase grip. The car has transverse leaf springs, so lowering height means placing lowering blocks over the leaf springs.

in the main european historic races e.g. lemans classic and tour auto the tires are limited to front 215/70R15 and rear 245/60R15 (avon cr6zz)