1965 GTO uses #1111054 distributor.
Initial timing is 6° BTDC.
Centrufugal advance starts with 1-5°@900 rpmīs, 14-18°@2000 rpmīs and max 20-24°@4600 rpmīs.
Vacuum advance #1116172 starts@8-10 in/hg and advances max 20°@14.75-16.75 in/hg.
These are @ crankshaft degrees and rpmīs.
This calculates total max 50-54° while driving at 4600 rpmīs.
Also, 1965 Tempest chassis shop manual are WRONG at page 11-33 regarding source for vacuum advance as ALL 1965 Pontiac AFBīs uses full manifold vacuum for the vacuum advance.
You will find the facts in Carter carbureter manual FORM 5482 june 1964 revised september 1964
I have found using fast centrifugal advance to compensate a too lean calibrated carburetor will never make full potential from the engine, but rather destroy the engine on long term usage. This is a thing of the past when leaded high octane fuels was available.
I prefer factory ignition settings for the engine and camshaft used and THEN adjust the carburetor idle/lowspeed circuit and main and secondary jetting for proper amounts of combustable fuel/air mixture. Especially for todays leaner fuels.
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1966 GTO Tri-Power
1970 GTO TheJudge
http://www.poci.org/
http://gtoaa.org/
Last edited by Kenth; 09-25-2021 at 03:03 AM.
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