360 /380 hp crate engine noisy valve train

What kind of oil are you running? Sticky lifters? A hydraulic roller cam shouldn't make much noise. I put a Hughs cam in my 360/300 and it doesn't sound any louder. You could check the torque on the rocker mounting bolts. Been fooled by header gasket leaks a couple of times. They can tick as if they were a valve train noise. Found them by feeling around for the air flow.
I`ve seen, and had hyd. roller cams that were louder than solid roller cams. the last being compcams in a hot 406 sbc. back then I talked to a chevy racer and mech. that has held an NHRA record 18 times over the yrs., and he said a lot of them do that. if everything is right in the valve train, I wouldn`t worry too much about it . you might try tightening the preload a little more, try one full turn. I did and it helped some. -----jfyi