Aftermarket valve adjustment

Hello-Im running edelbrock performer rpm heads/cam with aluminum roller rockers. I want to do some adjustments as it sounds like Im starting to hear a slight tap tap and my vacuum guage is bouncing a bit. Is there a specific order that they need to be adjusted in? If I do this with the engine NOT running how tight should I adjust them? Any advice?
PS Great website.

What cam package ?

The engine has edelbrock performer rpm heads, cam and intake with Crane 1.73 roller rockers. It has TRW dome pistons with 10.25:1 CR. Im running a 750 holley with an electric fuel pump. Fuel pressure is 5.5-6.5lbs. Timing is advanced 15 degrees. Vacuum is reading at about 10 inches. Idle set at about 900. Heres what Im running into - maybe/maybe not related. Vacuum gauge bounces at idle-like up to 5 inches. Lately when I shut the engine off it sometimes "runs on". The engine was built by a local engine builder with lots of experience and he was even perplexed. Its sealed up pretty tight which would make me think its not a vacuum leak. The builder even used a scope on it to see if he could hear a leak but didnt hear anything. Overall the engine MIGHT have 300 miles on it. It idles fine and going down the road it runs great. The main problem is sometimes when I shut if off its running on.

Timing? If you are hearing a tap tap with a hydraulic cam, you may be losing a lobe. Just guessing from afar.......

The heads are the 95 cc performer rpms. The piston part number is L 2443 I believe. When I ordered the heads summit said with the 95 cc chambers I would have about 10.25:1. I adjusted the valves tonight-a few were a little loose but nothing I would be concerned with. After we adjusted them the vacuum gauge was still bounces. I think I might try a different gauge to make sure I get the same reading. The engine runs strong. Its never missed or sputtered-if it had a bad cam what would be some symptoms?

The run on by my guess would be the strong compression mixed with the pump gas that is causing it. Its like preignition, the compression causes it to ignite being that the engine is already warmed up and what not. My 429 used to do it when bone stock, one time I thought I was never going to stall it. Might not be it, but I'm taking a stab at THAT or maybe the plugs are too hot of a heat range?

Someone step in, and if I'm wrong, then sorry about that.

An engine can run on only if it can continue to draw in fuel and air. In the 70's, with crappy fuel and crappier engines, the manufacturers used to cure the run on problem by putting a small electric idle solenoid on the carb's throttle linkage. When the ignition was turned off, the solenoid shut down as well, closing the throttle plates completely. When the ignition was turned on, the solenoid would open the throttle to the idle position. You might consider something like that, or.........

......you could shut it off while it's still in gear.

maverick wrote:An engine can run on only if it can continue to draw in fuel and air. In the 70's, with crappy fuel and crappier engines, the manufacturers used to cure the run on problem by putting a small electric idle solenoid on the carb's throttle linkage. When the ignition was turned off, the solenoid shut down as well, closing the throttle plates completely. When the ignition was turned on, the solenoid would open the throttle to the idle position. You might consider something like that, or.........

......you could shut it off while it's still in gear.

It had one, wasn't hooked up though I guess.