Originally Posted by nucci

Not sure if you know this, but the 255/35-18 Hoosier is less than 0.5" narrower in both case and tread widths than the 285/30-18 Hoosier. It is a LOT bigger than its tire size numbers suggest. If you were to accurately size it by the tire numbers, it would be something like 270/30.

Matt

Originally Posted by Dallas J

So I got bored at work and made a big excel worksheet plotting out rpm vs torque for each gear to find the theoretical best RPM shifting points (Need to manually input torque vs RPM though )

Anyways, it made it easy to just plug in a few numbers to find these out

Tire -- Dia. -- Speed @ 7500
245x40x17 -- 24.5 -- 61.9
275x40x17 -- 25.5 -- 64.4
295x30x17 -- 25.3 -- 63.9
245x35x18 -- 24.7 -- 62.4
255x35x18 -- 24.8 -- 62.7
285x30x18 -- 24.9 -- 62.9

This is for an Evo IX SE (My car of course). Tire diameters are from Tire Racks website for Hoosier A6's and ignore possible tire growths at that speed (Cause I dont know how much each one might grow if anything appreciable)

It seems the 295x30x17 would be a good tire as far as 17s are concerned, 1mph diff from the 285x30x18 and pretty much the same width (Tire Rack data again). Personally Im gonna run the 255x35x18 for a season while I get things sorted then get the 285's the next season.