big tire v big rim?

[911st]

What is going to be faster?

Running the largest tie that is recommended for a given rim size?

Or, the largest recommended rim for a given tire size.

For example.

For a R888 225/50 the recommended rim size is 6-8".

A 245/45 recomends a 7.5-9"rim.

I have 8" rims.

So what is faster assuming a proper rear suspension set up. The 225 or 245 if the only rim choice is the 8"?

[teenerted1]

two tires different sizes spinning at the same RPM????? the larger diameter tire would be going faster.
but your engine rpm will be different. and your speedo will be off unless you corect for tire ratio and gearing.

[GrantG]

Originally Posted by 911st

What is going to be faster?

Running the largest tie that is recommended for a given rim size?

Or, the largest recommended rim for a given tire size.

For example.

For a R888 225/50 the recommended rim size is 6-8".

A 245/45 recomends a 7.5-9"rim.

I have 8" rims.

So what is faster assuming a proper rear suspension set up. The 225 or 245 if the only rim choice is the 8"?

It's a close call. I would go with 225's on 8" rims (I do). I think I'd want 9" rims for 245's ideally...

[Bill Verburg]

Originally Posted by 911st

What is going to be faster?

Running the largest tie that is recommended for a given rim size?

Or, the largest recommended rim for a given tire size.

On a race car where there is no budget or class rule restriction you will always choose the tire & size you want run then fit the widest wheel that is speced for that tire.

In the real world that most of us live in compromises need to be made, but if I was going to go to the trouble of running R rubber I would want 225/ on 8s and 245/ on 9s

it's been a while since I used those sizes but there is/was a timeable difference

lately i've come to the conclusion that there is no advantage to a 275/ on 9.5 over 265/ on the same wheel.

[911st]

Bill, was hopping you were watching.

So for a Carrera with mild suspension and an 8" rear rim requirement, are you saying a 225 is a better choice than the 245 using a tire like the R888?

Is the 245 being bigger and approved for that size rim going to be faster given the righ settings?

Thx in advance.

[911st]

PS, who makes a 265/17 tire?