WildWolf

So.... "they" say with a lower sidewall (+1 or +2), you get better handling. How come Formula 1 cars and NASCAR have such big sidewalls???????????? Can someone please explain

mountainbiker2

It's just the rules that the govering body comes up with. Nascar still has carburetors. Fuel injection we know is better. 5 bolt wheels? Why not 1 center lug like the Formula 1,Cart and Indy cars. Some reasons for this is cost, marketing, tradition, ect.

Steve

Solofast

Mountain biker is correct, both rulemaking bodies have picked a wheel/tire size that a long time ago became obsolete.

Shorter sidewalls give you faster steering response, but not necessarily more grip. The trade off between steering response, lateral grip and tire dimensions could fill a couple of books. The need for bigger brakes has, for the most part pushed out the rim diameters on street cars, along with the advantages in steering response.. The trade off has been ride harshnes that the low profile tires provide and the bigger chance of damaging a rim on the street due to road hazzards. For racing, where grip is more important than anything else you will often see some pretty rubbery handling tires that are still very fast. The current Kumho's are much less responsive than the Goodyears or the Hoosiers, but they are faster in an autocross because they have more grip....