How fast are big block Duster's.

You are going to have to get as much tire under the rear as possible. Some sort of traction aid will be needed for racing at the track. Don't forget the required roll cage for you time class and the added weight. Roll bars are not light. My 14 point cage with a funny car head cage weighted about 175 lbs. plus the weight if the welding rod material. That 3:73 I think will get you high 11's-low 12's. That's a healthy street small block car......... As I see it, it's all on an individual basis The radicalness of your set up all depends on what you are willing to tolerate on the street. There is no utopia. There is only your own personal limit.