Why, on the 18" rims did Porsche go with 285/30's on the C2's but 295/30's on the C4's (and turbo's I guess)? Obviously, 295/30 is a better match in overall diameter compared to the 225/40's in front (.4 of 225 is 90, .3 of 295 is 88.5, .3 of 285 is 85.5? I mean, the difference's in handling and final ratio are going to be pretty small, the 295 is a nominal 0.4, inches wider and a whopping 1/8 taller, so it's pretty unnoticeable, EXCEPT that with 295's you'd get a little bit more rim protection, and they look nicer. I've owned the same size tires from a few different makers and Dunlops width is totally different than Michelins, which is different from Bridgestones, so THAT variation along is much greater than a single 10mm increase in width. Is the difference in understeer that much that such a small difference makes that much difference?
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YOUR RESEARCHMinor tire size question
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Porsche specs the same tires on the C2 and the C4. The C4S gets different tires because it has a "turbo" body and thus significantly different weight, track, and exterior dimensions from the other cars.
And the rear wheel on the C4S is 11" wide rather than the 10" rear on C2 and C4.
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Frankly, I'm wondering if it's not just cosmetic. Bigger fenders, bigger wheels to fill them out.
Quotes source post: 5330927
The wide body factor is certainly a major part of the appeal of the C4S. Porsche probably chose to build the C4S on the Turbo platform (rather than C4) precisely for the wide body styling, because it would be more visually distinct from the C2 and C4, and therefore worthy of a price bump and increased profit. Not to mention the cost effective ease of conversion: just take out the expensive dry sump Turbo 3.6 and drop in a standard 3.6. However, the Turbo's wide body is certainly not cosmetic, as it houses the intercoolers, and needless to say, the additional rear wheel width is helpful putting down the additional power. But back to your question....... What's the first comment usually made about the C4S? It's great looks.
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