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Old 10-27-2012, 04:09 PM
Zerocyde Zerocyde is offline
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Quote:
Originally Posted by F-BIRD'88 View Post
Ya just yank the distributor and re stab it in a better position.

To see the effect of the increased idle timing and help you determine the exact amount of idle timng your motor
likes, now , before you get and install the 10deg bushing, you can remove the distributor and temp lock out the mechanical advance system so its fixed. (read the directions) Set the now fixed timing at 34-36deg.
and get the carb all reset. Now move the timing around and find what the motor likes at idle. (best idle manifold vacuum) best throttle response and idle quailty.
( between 24 and full 36deg timing at idle). If it likes the full 36deg locked timing, and does not protest at low rpm full throttle ( lugging the motor) then go with it. If it does ping a bit if when you lug the motor down
then go with the short timing curve.

You can check and determine what the motor likes by driving in first gear with no throttle input
idling along with clutch out in first gear. ( this is similar to what the motor sees on a automatic trans, while idling in gear.

Again as long as the motor does not ping when lugged, while using locked timing, you re good to go.

Locked timing ( no mechanical advance) + 10deg of vacuum advance.
Install a ignition power interupt switch if its hard to start up when hot with locked timng.

BE SURE the GM starter motor brace/bracket is installed.

try the locked timing. Those thumpr cams need lots of timing at idle. ( EGR effect at idle of the narrow LSA, extended ex duration and high intake/exhaust overlap)
This is a great idea, I'm gonna go try this.
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