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Old 03-28-2012, 03:51 PM
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Yes fix the distributor exactly as I posted, so many many times.

The way you got it now is not right at all.

Fix the mechanical and and vacuum advance systems.

24deg base at idle 34-36 at max mechanical

10 to 12deg vacuum advance at part throttle cruise hiway speeds and rpms
not all in at idle.
having the vacuum advance pegged all in at idle is not correct.

use ported vacuum.

if you use full manifold vacuum as a signal source, you should adjust the vacuum advance so little or no vacuum advance is actually added at idle.
and the vacuum advance does come in at hiway cruise speeds at part throttle light engine load Make sure it does not ever exceed 12-15deg at highest manifold vacuum (deceleration) by ensureing the vacuum advance travel is physically limited to 12-15deg.
if it pegs the vac advances at idle its not right, reguardless of what you have read.

Find the best rate of vacuum advance by adjusting the vac adv diaphram tension.
a tach and vacuum gauge helps get it dialed in right.

The way you got it set up, without specific limits on the advance travel of BOTH the mechanical and vacuum advance systems can and will result in possible-probable engine damage from excessive spark advance on WOT shifts and down shifts from high speed.

consider yourself for warned.

Last edited by F-BIRD'88; 03-28-2012 at 04:11 PM.
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