97 cobra severe tick new shortblock

i rebuilt the engine that was in the car it had a rod knock real bad i put new crank rod and pistons in it i just got it done. now it has a valve train tick sometimes it goes away??? dont know whats going on but surely pissing me off!! i hear pcv i hear new heads i hear retorque cam ladders?? ne one have an idea? also im running 5w20 valvoline vracing oil i see some peeps are running 10 30??

97 cob severe tick/cams

its actually the opposite it seems to be it is not there when i first fire it then it starts slow then gradually becomes a constant noise it is spinning at the camshaft speed fore sure not to mention i have rebuilt the complete lower end of this motor. thats why i was thinking as the oil thins when it is warm a lash adjuster(lifter) is collapsing under thinner oil conditions??
but its surely pissing me off i got the car last friday with a blown motor and have been working my ass off to get it straight but it seems one thing after another. i have changed all lash adjusters and rockers or cam follwers and going to try this!