if youre racing and cruising a car, with an emphasis on cruising (80% cruising, 20% racing), a nice stall is around 2800-3200. my 3500 is a bit much, but you get used to it...also, for cruising, i would not go with a 4.56 rear, unless i was running an overdrive transmission. 4.30 is the biggest that i would deal with, especially if youre going to be on the highway at all...my 4.10s were really nice for cruising.