Hello All. I have just completed a rebuild on the stock L-82 in my 73 Z28. I am having trouble getting the engine to idle smooth and consistent. Does anyone know how much manifold vacuum I should be getting at idle in gear? Also, the GM book calls for valve adjustment to be 1 full turn past zero lash, which sounds awful tight to me. I have them set a zero lash right now which could be partially responsible for low vacuum readings I am getting (5-6" Hg in drive @750-800 rpm). Motor is numbers matching and bone stock, GM factory spec cam, valves, ect. Only variation is .060 over on the cylinders. I have extensively searched for and eliminated any vacuum leaks that I can find. I have found that the vac advance on the distributor is wrong (requires too much vacuum to operate) which I am replacing this weekend. Just trying to eliminate all possibilities before looking to the carb. Thanks in advance for any help. Even though I am newly registered to this site, I have been using and reading it for years. Hands down, the best site out there (not just Camaro sites, ANY site). Your tecnical info has been invaluable during this frame up. Keep up the good work.