ok the question is... how? how do you set the total timing with a h.e.i. with vacuum advance??? i got "a few" responses to my earlier post(like 3 or 4?) and they all said to unplug your advance to set it but,.. if thats the case when you plug it back in then you'll have a bunch of extra timing that wasnt accounted for. that could cause some problems. so how do you set it with it still hooked up ?? or do you even leave it hooked up?? whats the procedure? i DO know you rev it untill it quits advancing(mine is out by 3000) then you look on the timing tape and just set it.

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89 firebird formula

356 10.5:1compression
comp cams xe262 cam
performer rpm intake
#1405 edlebrock 600
sportsman 2 heads 64cc 2.02/1.60 valves 200cc intake runner
msd 6al
h.e.i. proform 50,000 volt vac. advance ditributor
700r-4 with 3.08 first gear and 3.23 posi 7 5/8 rear end.
b trans shift kit(will kill shifts...suck dong!!)
shorty heddman hedders with custom 3" pipe y-pipe back(no damn cat!) with 40 series flowmaster!


future mods: 406 roller REALLY REALLY REALLY RADICAL!!!!!

 

Listen to the other post...I think one of them was right on...but with the vacuum advanced plugged in, and cruising down the highway at say 2000 RPMs, you'll have vacuum advance pulling in 12-16* and the mechanical advace bringing in another 30-35*..."wait" you say, that's 45-50* advance? Yeah, but when you mash the throttle, you lose vacuum, and mechanical takes over. The additional advance you're getting at part throttle and cruise conditions, is aiding you in MPG's.

Do as you were told before, disconnect the vacuum advance (plug the open vaccum port), what you want to set is the mechanical advance to be 30-36* BTDC, where the motor likes it best..in the 2500-3000 RPM range again, depending on what the motor likes.

 

ok i know this sounds stupid but... wont it have detonation if you do that? i now understand that the vacuum pulls away at WOT and that helps alot so if i do it this way it will set the total timing? i know i sound stupid but,. im sort of understanding it now(sort of!). thanks for the post it helped alot!! ill go try that after i clean my carb today!!

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89 firebird formula

356 10.5:1compression
comp cams xe262 cam
performer rpm intake
#1405 edlebrock 600
sportsman 2 heads 64cc 2.02/1.60 valves 200cc intake runner
msd 6al
h.e.i. proform 50,000 volt vac. advance ditributor
700r-4 with 3.08 first gear and 3.23 posi 7 5/8 rear end.
b trans shift kit(will kill shifts...suck dong!!)
shorty heddman hedders with custom 3" pipe y-pipe back(no damn cat!) with 40 series flowmaster!


future mods: 406 roller REALLY REALLY REALLY RADICAL!!!!!