Cam removal and install without removing heads?

All stock it’s a 318 30 over, so basically whatever a stock motor can handle is what I’m looking at. I know I cannot check it that’s why I looking for information on what a stock 318 can handle.
Id stay under .440-.450 lift the clearance on my 318 heads (valve to retainer) is .487 im not sure about the valve to piston clearance i didnt get that far.