Originally posted by: Zenmervolt
Originally posted by: SampSon
I don't see many professional racecars using low profile tires at all.
That's a result or rules. There is a restriction on maximum wheel diameter and in order to get the tire diameter large enough so that it works with gearing the sidewalls have to be taller. That's why F1, IRL, CART, and NASCAR cars run tires with higher profiles. Watch an ALMS (American LeMans Series) race and look at the tires on those cars. They're all low-profile because the rules allow them. Additionally, F1 tires are so wide that they actually are low profile.
An F1 tire is 660mm in outer diameter. The maximum wheel diameter is 332mm. This means that the sidewalls are 328mm in total. This is a 164mm sidewall height. An F1 tire is 380mm wide for rear tires and 355mm wide for front tires. That means that F1 tires are 380/43 R 12.9 (we'll call it 380/45 R13 for convenience) rear and 355/46 R 12.9 (again, we'll call it 355/45 R 13 for convenience). That means that F1 tires are actually 45-series tires, which is definitely considered "low-profile". They're just so much wider than street tires that they're taller (45% of 380 is a lot more than 45% of 225).
ZV