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geezer#99 · 02-13-2013, 01:10 AM

Sounds right. 'A' means advanced which means btdc. Unplug your vacuum line from the distributor, set your initial at 12 and plug the vacuum advance back in.If you plug it into full time vacuum your timing will advance. If you plug it into porte then it won't advance till you open the throttle.
Ported is on the plug on the top passenger side of your holley. Advanced would be at the bottom on the throttle plate.

02-13-2013, 01:10 AM	#2
geezer#99 Registered User Join Date: Aug 2009 Location: Bowser Posts: 13,783	Re: Help with timing issue Sounds right. 'A' means advanced which means btdc. Unplug your vacuum line from the distributor, set your initial at 12 and plug the vacuum advance back in.If you plug it into full time vacuum your timing will advance. If you plug it into porte then it won't advance till you open the throttle. Ported is on the plug on the top passenger side of your holley. Advanced would be at the bottom on the throttle plate.