Adjusting Rockers While Engine is off?

[funvairs]

I think you should check the timing and dwell. They are both part of a basic tune-up. FWIW, none of the 9 Corvairs that I have, idle like a muscle car.
All of them, except the Ultra Van, have stock engines

[jmikulec]

I did do the timing but that was before brand new carb rebuilds from Clark's. So I am sure that It needs timed again.

[Vin]

One thought going back to where the issues started...you said you tightened the rockers down until they wouldn't move (zero lash) then 1/2 turn more. If you set the number 1 cylinder at top dead center then rotate to zero etc.... and used that cold procedure (there is a good old video on YouTube) you should be fine in theory but there is something in that process that can mess a person up. If you tightened the nuts down until literally there is no movement of any kind you may have way overtightened. Zero lash would mean that you can't push or pull the rocker up or down. You are hunting for the point where it just tightened to that point. But some people will incorrectly wiggle the rocker arm side to side and tighten it until there is no sliding or side to side motion left. If that is what you did you may have gone way past zero lash. At the point where the rocker arm will not move in and out (zero lash) the rocker arm will still slide or wiggle some side to side and that is ok. Know the difference between the two movements and what you are feeling. You may want to redo this if you are not sure.