if you are going to race,chevy motors are the best way to go.it is still general motors and i have dealt with many people that can get the birds to do 6es or 7's with an inexpensively built chevy motor.personally,i would never put a chevy motor in any of my birds but you have to be realistic.chevys are alot easier and cheaper to build.go to the track and see what the quarter mile racers are using for a power plant.the ones that are winning are using some form of a chevy motor in most cases.