With regard to putting a high torque cam like a Comp Cams H260 (212º, 212º,.447", .447") in my '72 302; with the increased lift, I probably have to worry about valve-to-piston clearance, right. What is the best way of checking this before buying the cam? I am not sure what pistons I have...they are the stock '72 ones but I can't remember if they were dished and/or had valve reliefs.

Do I have to worry about valve springs or rocker arms binding?

 

Piston to valve clearance should be no problem with a cam like that. You have to get a lot more radical than that to run into problems. I would definitely go with new valve springs. Old springs don't like new cams with more lift. Coil bind shouldn't be a problem either with only .447 lift. The pistons will have valve reliefs ( the dish doesn't count as valve clearance ).