I have a Saito .62 in mine. I would imagine you could put the saito .72 in it but getting in balance at the recomended 4 inch CG may be a little difficult. And really the plane doesnt need as big an engine in it as i put in it. A .46 is major power for it from what i have heard. its not a real heavy plane. mt superstar 60 trainer has a saito .72 in it and it is over powered and weigh alot more then the pitts 40.

But you can do anything you put you mind too. but i would say the saito .62 is to much for the plane gonna find out tommarrow if it is or not..