Ok, Phil, since you're posting it again ...
> A rule of thumb is that the rim
> > width should be at least 70 percent of the section width.
Is that for high profile tires or low profile. Definitely makes a BIG
difference.
High compliance sidewall or low ?
Steel, nylon or polyester ? What about combinations ?
How about load rating ? Again, it makes a difference. Corner caps ?
Bottom line, if you're going to slavishly follow the rules, at least find
out what they are ! Every single tire maker (at least all the DOT approved
ones) gives a range of suggested rim widths for every model and size of tire
they sell. AND the suggestions aren't always the same between different
models of tire even in the same width (as I suggested above).
> but I am saying that the combination of
> > over-wide tires for the wheels, the camber-challenged TR4 stock front
> > end, and the whippy wire wheels probably add up to a setup that would
> > not be any faster around the old skidpad than the 165s.
Care to place a small wager on that ? Make it worth my time, and I'll prove
you're wrong ... just in case you missed Bill's post about what happened
after he took my advice on tires : first in class at the VTR autoX.
Granted, it might not be due to the slight increase of tread width on the
road. IMO the main argument for running low profile tires on a TR is that
the stickier tire compounds and constructions are only available in low
profile. Check out the 'performance' sections on TireRack.com, they simply
are not available in 80 series tires, and usually not even in 70 series.
Randall
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