First my apologies to Jack for mis-spelling his name! It is Costella from now on! Regarding Jack's design philosophy, I may not completely agree with it, but as Jack said, it is pretty hard to argue with the results! And remember many of the records that were set by Jack's cars were by over 50 mph over the existing record!!! Also there are some other non Costella cars that follow Jacks flat bottom design that are going pretty fast, Potett and Main's 436 comes to mind.
Rex