1980 Vacuum Question
Thread Starter
Heel & Toe
Joined: May 2007
Posts: 16
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1980 Vacuum Question
I removed all of the smog equipment off my 1980 vett.
I was careful not to remove anything I was not sure about. Doing this I expected troubles with vacuum.
So here are the two things I need help with and they may be related.
1) The vacuum advance on the distributor used to go to the old air cleaner. Where does it go now? Which port on the stock carb?
2) The transmission does not shift into 3rd.
Thanks
Terry
I was careful not to remove anything I was not sure about. Doing this I expected troubles with vacuum.
So here are the two things I need help with and they may be related.
1) The vacuum advance on the distributor used to go to the old air cleaner. Where does it go now? Which port on the stock carb?
2) The transmission does not shift into 3rd.
Thanks
Terry
Tech Contributor
Joined: Aug 1999
Posts: 14,379
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
The vacuum advance should never have been connected to the air cleaner. It normally connects to the thermal switch on the thermostat housing, and this, in turn, is connected to the carb. If you intend to bypass the thermal switch, run the vacuum advance to any of the manifold vacuum ports on the carb. All ports are manifold vacuum except the ported vacuum port located at the forward passenger side corner of the baseplate. In stock configuration, the vacuum advance pulls vacuum from the forward driver's side port on the carb. This is manifold vacuum, so use it - it wil be correct and stock.
Make sure your tranny modulator line is still hooked up to manifold vacuum.
Make sure your tranny modulator line is still hooked up to manifold vacuum.
