1981 timing
Melting Slicks
Joined: Apr 2009
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From: Great Plains Iowa
Racer
Joined: Oct 2001
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From: Portage La Prairie Manitoba
Melting Slicks
Joined: Dec 2009
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From: Thunder Bay
Like any other small block chevy you can set up the ignition curve to provide about 35 degrees of total advance, all in by about 3000 rpm. The vacuum advance should give you another r16 or 18 degrees of advance. Those smog motors in the late 70's and early 80's were set up to run so lean you may run into detonation problems if you advance the timing unless you take steps to richen up the mixture.
Heel & Toe
Joined: Mar 2016
Posts: 22
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From: Norfolk VA
Vacuum Gauge
[QUOTE=2tone81;1591737000]Emission sticker and service manual call for 6 degrees. btdc. Is there a better setting? All stock and emission crap still hooked up.[/QUOTE
No matter how stock the engine will be there will always be differences between all engines. even two fresh engines out of the factory. because of tolerances that are allowed on mass produced engine. usually the best way to go is hooking up a vacuum gauge up to either a manifold, or carburetor base vacuum line. that way the engine will tell you what it wants for timing based on the max vacuum possible. start at the 6 degree mark and move the distributor around once you find max vacuum i usually retard the distributor 1 or 2 degrees.
No matter how stock the engine will be there will always be differences between all engines. even two fresh engines out of the factory. because of tolerances that are allowed on mass produced engine. usually the best way to go is hooking up a vacuum gauge up to either a manifold, or carburetor base vacuum line. that way the engine will tell you what it wants for timing based on the max vacuum possible. start at the 6 degree mark and move the distributor around once you find max vacuum i usually retard the distributor 1 or 2 degrees.
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Race Director
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
If it's bone stock I would follow what is in the specs. However you might add 2-4 degs to help it out. 
Last edited by MotorHead; Mar 10, 2016 at 11:54 AM.