I've been thinking about this one for awhile, so I thought I'd get some opinions.

The BSP folks seem to be gravitating towards the 285/30-18. With limited final drive options, it's nice and short, has a lot of width, and a low sidewall.

The SM folks are moving towards the widest damn thing they can get their power-hungry little hands on :evil2 Makes sense, choose your final drive and gearing is irrelevant - and a lot of power demands a lot of power.

What about DSP? Most of the big dogs have been going the same route as BSP, potentially as lemming syndrome (which autocrossers are good at) after Fauth won last year.

I've been thinking about doing a set of 16x10s with either 265/45 Kumhos or 275/45 Hoosiers. They're a little bit taller than a 285/30 (2 mph). They'll also theoretically be lighter. Light 18x10s are no less than 20 lbs, whereas 16x10s can be had at 15 lbs. The big unknown to me is the effect of sidewall height. A 45 vs. a 30 is a pretty significant difference. The 45 will have a contact patch at least as long as the 30, but not as wide. The Hoosier carcass has really stiff sidewalls as it is.

So my questions: What kind of effects do sidewall really have? Can it be changed with other setup attributes? If I can swing a 16 with a good amount of patch, small gearing difference and a good weight advantage at $250 less per set, are a set of 18s and 285s really better? Are there any factors I'm missing here?

And does anybody know of a listing of Hoosier/Kumho tire weights?

You know, I've been thinking the same sorts of things. I think even more telling is that the difference at 4K RPM in 2nd is ~1MPH. I know that running STX with 245/40-17s I've bumped the rev limit a little too much for my liking this past year, so an extra 2MPH might not be a bad idea with the higher speeds we seem to be seeing.

If you get any private responses and want to share, PM me or make a new post.