Well, not many "street" cars truely pull very well above 6,000 rpm. The factorys put cams in them to be useful in the rpm range where we normally use them for their intended purpose, the street. Just because you pull it onto a race track doesn't mean that it will now "pull strong to 7 grand". Well, at least not with the stock componants in place. If you keep your ears open it is pretty easy to pick out the ones that do.