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Hey guys, on my shop truck I was doing some tuning on it, I check the timing its a 350 stock as a clock it was spot on 10 degrees, after I checked it I plugged the vacuum advance back which has manifold vacuum and I noticed it did not change the idle, so I put my vacuum hand pump on it and it would not do anything, so I put a new one on and when putting the plug wires back on I noticed # 1 was 2 spots or position to far clock wise, its HEI its were #4 would be. I have thought this through probably to much, but my question is, is the truck at 10 degrees or is the wire placement throwing the timing different than its showing? like I said i have over thought it, I remember my dad saying you can make #1 which ever you want but ? if its fine great I would like a little reassurance, great tuners on here, thanks in advance guys.
Lane
Doesn't make any difference where #1 is placed on the cap.
However, sounds like your vacuum advance isn't working. I'd investigate that. Could be that the diaphragm within the vacuum can is ruptured or something is "frozen" inside, preventing it from working.
Someone may have re-indexed the wires to accommodate the HEI distributor......if it wasn't stock....
The only "rule" is that the the rotor should be pointing at the #1 cylinder plug wire tower near TDC....how the rotor, distributor and wires are arranged to make that happen can be anywhere. The convention is that it be a certain way but its not required.
It does sound like your vacuum can was shot but make sure you are operating of full manifold vacuum (from somewhere below the carb throttle plates); "ported" vacuum configurations don't pull vacuum at idle as they are tapping a feed above the carb throttle plates...
Last edited by Frankie the Fink; Dec 12, 2018 at 06:55 AM.
Plug wire location
