ive heard different things from different people maybe you can help. non HO's came with flattop pistons and it is not possible to run much larger than a stock HO cam due to valve to piston clearance issues. is there any truth to this. also im having problems with my check engine light coming on and a very rich smell during startup. what im told is that is because i have a non-HO longblock with an HO intake, computer, and (what they say is the problem) map sensor. is that the problem or is it something else.