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Had my engine rebuilt. Car started fine and does run, but when I went to adjust the timing the car would stall when I moved the distributor to where the hash marks are. On the block the tab had 4, 0 and 6. Any help on how to set this would be much appreciated. I assume that I have the distributor in the right way as the car can be driven.
 

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When you change timing you usually also have to adjust the idle speed on the carb.
'Factory' specs on these cars usually called for (if I remember correctly) 6 degrees initial.

The 'right' way to do it is to use either a timing tape on the balancer (very important to use the correct tape, installed correctly!), or use one of the fancy timing lights that can check total advance --- then disconnect and plug the vacuum advance hose, run the engine up to about 2500 rpm and hold it there, then set the timing at 35 degrees and lock it down. Then measure it (don't change anything) at idle just so you know how to get BACK to that setting in the future. Reconnect everything, fine tune your idle, etc.

Finding the best setting for your car requires some trial and error and track testing against an accurate clock. 35 degrees is usually a good starting point.

Bear

Bear
 

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What make and year engine do you have?
A 1968 Pontiac V8 timing tab should have 0, 6 and 12 degree marks on the tab.

If you tried to adjust the distributor at idle with the vacuum advance still connected, the engine would definitely not run well, if at all.

To set the timing at idle the engine must be at operating temperature, the vacuum advance hose must be disconnected and the vacuum source line must be plugged.
 
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