This thread took an interesting turn, talking about manifold vs. ported vacuum. I'm not worried about how well the engine runs at idle, it works just fine with ported or manifold vacuum, and does not ping at idle or when moving the throttle to various engine speeds when parked. It was only pinging when I was accelerating somewhat rapidly between 35 and 50 mph. So I backed the timing down to 7 BTDC. Under that condition (acceleration), it would not make any difference if I was connected to ported or manifold vacuum. But with the load I was giving it while accelerating, if the vacuum advance was retarding the timing at all, the 23 degree can would have retarded it even more than a 15 degree can. Apparently it was not retarding the timing enough to prevent the pinging under load, so a 15 degree can would not make it retard more under load would it?
Quote:
Originally Posted by RichardJ
Your method of retarding the timing two degrees at a time until it stops pinging is as good as it gets for a stock street engine. Did you do that with the vacuum advance removed/plugged? You should.
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Yes, with the vacuum advance removed and plugged, adjusted until it stopped pinging. Then took it for a test drive and came back and adjusted to further retard it until it didn't ping when accelerating while driving. I didn't think of towing anything or putting a heavy load in the bed and repeating the same test. If I do that, I will probably end up at the factory setting of 4 BTDC.
Quote:
Originally Posted by RichardJ
Just simply get rid of the 23* can. Something closer to 15* or 10* or an adjustable can.
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What would that do for me?
07-17-2018, 07:26 PM
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