I will be very succinct......

My 1987 911 Carrera in F prepared class

The previous owner, {a very well respected Club racer with the class LRP record in this (now mine) car}, specifically
stated that on this car I should get Hoosiers R6s 225 front/ 245 rears end of story....... don't bother with what everyone else is running (R6 245/275).

So.......I am going to stick with his advice since he is done very well in this car and others that he raced........

.....but is there anybody in this distinguished forum who can explain in simple terms the obvious differences btw. the 225/245 vs. 245/275 set up?

Thank you.....

 

Fitty-tree pages.







Professional Racing and Driving Coaching
Do you want faster lap times?

 

Is that the setup he ran when he set the lap record? If so then run it, if not then run what he ran!

 

I just spat pepperoni pizza and a gatorade all over my monitor!!!

 

Just trying to learn for those more experienced than me......

 

less rolling resistance?

 

Wider is not always better...a bigger tire will have a taller sidewall and therefor will tend to roll over a bit more, and tend to have more sidewall flex which can make the car turn in less sharply in the front and give a mushy feel to the rear. The other issue is the width of the tire vs the size of the rim may not be correct which forces the sidewall in on a too narrow wheel and can amplify the problem.

 

Don't forget that Ronnie raced that car 5+ years ago...technology marches on. Ronnie raced on R3s not R6s.

 

..

 

Good point Geoffrey......

 

...can I change my answer?... Is this for a race? like against other cars? on a track? what kind of air were you planning on using?...

 

Correct. Many folks who race BMW's have found that they are often faster (especially on more open tracks) with slightly narrower tires than you'd expect or than they could fit, for example using 235's instead of 255's.

LMAO about the air comment.







Professional Racing and Driving Coaching
Do you want faster lap times?

 

Very reasonable approach! And , therefor, you have answered your own question since the PO is much more experienced than you, ran the car very successfully, and said you should run 225/245, as he did.

 

yes, yes, yes, air......

 

And run R3's