distributor vacuum

k i also just posted this in a older thread i started but figure id start a new one... when i plug the vacuum line in off the side of the carb... the engine dies and runs like crap... any ideas on why its doing this??? its a brand new 351 i just dropped in... with new distributor.. i think the carb is a 4b holley 650.... not sure whats going on so i just test drove it about 10 miles with the vacuum off

See my answer in your other thread.
Basically though, you need to hook it to a port on the carb that does not have any vacuum signal when at idle. If you hook it to full manifold vacuum, it might be taking the timing so far advanced that it won't run right.

In other words, simply hooking up the vacuum advance at idle should not effect it in any way. Much less stalling it out.

Verify that first, then we can move on to other things. Hopefully that fixes the issue though, but you need to put a light on it and see what's going on.

Paul

DirtDonk said:

If you hook it to full manifold vacuum, it might be taking the timing so far advanced that it won't run right.

In other words, simply hooking up the vacuum advance at idle should not effect it in any way. Much less stalling it out.

Verify that first, then we can move on to other things. Hopefully that fixes the issue though, but you need to put a light on it and see what's going on.

Paul

Click to expand...

I'd agree. If you have, or can get, a timing light--that will help.