Road racing wouldn't you want quick revving and top end rpm vs just big cubic inches? Seems like a very expensive way to get there as well? Buicks, Olds, and Pontiacs cost $$$ to build.

I look at engines like that with all the trick do-dads and then look at how fast the F.A.S.T. class guys run with no real visible speed parts and it makes me wonder how much of the trick looking stuff does one really need?