Distributor vacuum advance issue

Hi Guys. A little background. I have a 1970 AMC Javelin with a 360 engine and point type distributor. I believe its the "AMC" dist, not the Motorcraft one they also used. I have the edelbrock performer intake and 1406 4-bbl, and am hooking the advance up to the "non-emission control vehicles" port. When I tried the "timed for emission vehicles" port there was no noticable difference than with the advance disconnected.

When I set my timing according to the tech book (5 degrees btdc with advance plugged) and subsequently reconnect my advance, the mark jumps up off the readable area, above the tdc mark somewhere. When I rev the engine, it eventually works its way back down to around the 5 degree mark or so as long as it stays revved. If I leave it disconnected and rev it advances to around 15-20 which I suppose is normal. My distributor has two vacuum connectors on it, one at the usual place and another jutting out the side of the advance diaphragm. I am plugging into the one on the side because that is where it was when I got the car. The other connector doesn't seem to do anything but leak vacuum so I am guessing its a breather hole or something. Do I have the correct advance & distributor for a 70 model 360? Is this spark activity normal? Forgive me for sounding ignorant about this guys but I came from the world of military diesels, where things like vacuum advance and ignition timing don't exist

Reply to
Gary H.
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You will get smoothest accelleration and best power band range if you put the vacuum line to "ported " vacuum. No vacuum at idle, vacuum as you open throttle slowly. It sounds like you have it to manifold vacuum. Set timing a couple of degrees high. Try 7-8 BTDC with line off and conect line and test drive. You want to keep the timing low enough to not get any pinging. You will lose a lot of performance and efficiency if the timing is too low.

Reply to
Uncle Dodo

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