Camshafts and clearance

The motor is in my shed is a long block,almost ready to be put in the car and I want to put a new camshaft in it for I know what I have instade of thinking whats in the motor. I got the single plane air gap intake for it and 202/160 915 heads. I was thinking about going 750-850 carb. The motor came out a duster that that they said it ran 7.40s but who knows I didn't see it.The motor was in a Ram charger with stock 355 gears and 40 grounds hawks and the motor turned them like it wasn't nothing.

So the motor might be 30 over with aftermarket pistons and rods. I havent had it apart yet. But its coming I'am doing new rod/main bearings..So what cam would you go with. the 508/509 hyd.
the air-gap is a dual plane intake.pull the cam out and see whats stamped on it if anything.