Well since its the new thing to do i guess ill give the turbo stuff a try. I have a small block (little m) 400 with dart cast 230's, super vic intake, all the goodies. The car is a 81 malibu 3300# with me in it, 400 turbo tbrake and 3.50's in the rear. The car is on nitrous as of now best pass is 6.4 @112 looking to improve this quite a bit. Im not sure if the s500 would benfit over the s400 for my build. what do you guys think.