The engine rules are great in my opinion! Flat lifters, No roller cams, wet sump, spec head. Someone can spend 7000 if they want but but not required. build your own motor and have it sealed. I think it can be done for 4000 to 5000. Roller cam setup is the biggest problem for failure of the 410's. roller lifter with the bar that prevents rotation is a weak point. these break and destroy other components.