Quote:
Originally Posted by Maynard
FWIW, contrary to the marketing hype (and about 3/4 of the posts on here) the contact patch SIZE is always the same (at the same pressure and car weight) regardless of whether it is a 205 or a 255 - it just gets longer and narrower on a narrow tire (best for heavy rain/snow). Wider tires don't put more rubber on the road, just on the wheel.
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I've come across this before, and for some darn reason I never remember it. Maybe that's because I'm all about wider being better!
I went to a remarkably comprehensive tire calculator page to find the contact patch sizes for the 245/35-18 that came on the rear of my car and the 205/50-17 tires that came on OP's car. The difference was 2.2%, or virtually nil for our purposes.
The calculator is on this page:
http://bndtechsource.ucoz.com/index/...alculator/0-20,
and this is its input form:
and these are its static and dynamic output forms:
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