Originally Posted by
36 sedan
If the motor is running poorly check the following;
The Check firing order to plug order, incorrect order will cause low vacuum and poor performance.
Check compression, low compression will cause low vacuum and poor performance.
Check carb adjustments, poorly adjusted carburetor will cause low vacuum and poor performance.
Check valve lash adjustment, out of adjustment valve lash will cause low vacuum and poor performance.
Check exhaust pressure, as mentioned exhaust restriction will cause low vacuum and poor performance.
Watch timing marks at idle to see if timing is fluctuating, up/down, timing mark fluctuation means there is too much movement at cam or distributor. Cam or distributor fluctuation will cause poor performance.
Set timing by TOTAL timing method, incorrect timing will cause all sorts poor performance.
Go to work on it and tell us what you find...