What could cause this? 360 problems ####update####
Not piling on and not sure if this was just a cam swap or total build. I always check piston to valve clearance with play dough. Actually, anything that can be measured or checked, I do. I have trust issues. Paint you a picture, build it, run it and something is “off” anything you didn’t actually check is now “totally unknown” and it will probably suck to measure/check it now. The setup to degree a cam is “time consuming” part. Not really, but once set up, I will do it twice, just to be sure my numbers are repeatable.