well i just built my 350 a couple monthes ago and i have a few thousand miles on it. i had a rocker arm stud pull out of a head and got a new head since it was under warranty.

everything was fine for a while but now i am getting this knock. it increases with RPM. i checked the valve lash and took the pushrods out and rolled them around and none are bent. i can hear it in the headers. you can hear it at idle and more throttle means louder (until a certain point) and more often. oil pressure is 50 at start up, 20 warm idle, 25-30 driving around. temp holds fine, no mixed oil and coolant, no leaks.

any ideas?

 

what were your clearances?

 

Exhaust leak tick?

 

Try pulling spark plugs wires and see if the noise gets louder. That will tell if it's a rod. Mains are a little deeper sounding. Although with the oil pressure you've got I question it being a main bearing.

 

everything was new. mains werent oversized. rods, and crank were brand new.

could be exhaust tick but its more of a knock.

i'll try the plug wire idea and see what comes of it.