I recently purchased an air boat that is powered by a 350 SB. After doing a few things to it I noticed that the intake was a Edelbrock Torker with a Holley carb. From what a friend of mine is telling me it also has 305 heads on it, with hedman headers. I did some research on using 305 heads on a 350 and I do realize that could be bad in several ways, but anyway I called a chevy dealership with the numbersfrom the block and was told its a late 60s to early 70s motor.(all iron) it also has Edelbrock valve covers. When I purchase the boat from my brother he told me that they guy he bought it from said it had a aftermarket cam.The engine runs great and I was just wondering what type of horsepower and torque do you think I am getting? I know that is hard to say with the info I am giving you but if you had to guess what do you think? Is there a (EASY) way to tell if an aftermarket cam was installed. Should I put 350 heads back on and if so what should I go with?thanks