For the longest time I could not figure out if my 84 Z28 Carbed 305 H.O. was suffering from an exhaust leak or a valve tap. The tapping remained after I tightened the passenger side headder bolts on my edelbrock headders. The tapping comes in and out at all different engine temperatures from cold to operating.

Assuming it is a valve tap, it has gotten worse I havent had a chance to really do anything about it until now, i have driven the car for probably over a year, mabe 10,000 miles with this problem. but like I said it doesnt do it all of the time.

If i am going to go through the trouble of removing the valve covers to tighten the all 16 valves down.... will it even fix the problem, or did I wait too long. If so what should I do, would buying replacement rockers solve this... or should I just leave it alone and put thicker oil in for now... I only need 1 more year of driving with this car before it goes into storage for a long time.

 

Has the engine been abused or neglected? Regular oil changes?

You might try changing the oil/filter and using one quart of ATF in place of one quart of oil. If the problem is a dirty/gummed-up lifter, the ATF may clean it up.

If it is an adjustment problem, don't just tighten all of the rockers - adjust them properly.

It could be a bad lifter, worn cam lobe, worn rocker, worn pushrod, or pulled rocker stud. Or, a backed-off adjustment nut that has lost its self-locking capability.