vacuum advance timing?
Melting Slicks
Joined: May 2006
Posts: 2,364
Likes: 103
From: Centerville Louisiana
Melting Slicks
Joined: Jul 2004
Posts: 2,577
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From: Long Island New York
Advanced
Joined: Mar 2007
Posts: 57
Likes: 0
From: SACO MAINE
Vacuum Port Timing
In Most Cases, The Vac Advance Is Tapped Into "ported" Vacuum. This Is Located Just Below The Carb. Throttle Plates.
This Is Not Done Or Used Most Of The Time On A High Performance Application (most Of The Time)
All Depends On How Much Total Advance You Want And When You Want It. You Need To Go With What Works For You Level Of Performance Gear.
This Is Not Done Or Used Most Of The Time On A High Performance Application (most Of The Time)
All Depends On How Much Total Advance You Want And When You Want It. You Need To Go With What Works For You Level Of Performance Gear.
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
If you want vacuum advance at idle to help idle quality you need to take vacuum off the intake or base of the carb.
Taking the vacuum off the side of the carb only gives you vacuum advance while running down the road and NO help at idle.
All cars need vacuum advance and it really helps idle quality.
Taking the vacuum off the side of the carb only gives you vacuum advance while running down the road and NO help at idle.
All cars need vacuum advance and it really helps idle quality.
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Racer
Joined: Apr 2006
Posts: 340
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From: Warrensburg MO
If you want vacuum advance at idle to help idle quality you need to take vacuum off the intake or base of the carb.
Taking the vacuum off the side of the carb only gives you vacuum advance while running down the road and NO help at idle.
All cars need vacuum advance and it really helps idle quality.
Taking the vacuum off the side of the carb only gives you vacuum advance while running down the road and NO help at idle.
All cars need vacuum advance and it really helps idle quality.
Tommy
Drifting
Joined: Aug 2007
Posts: 1,924
Likes: 6
I'm pretty sure timmed is a typo for timed (or ported, variable etc)
In the Holleys and Edelbrocks I've had over the years, you would connect the distributor to the ported vacuum. Typically this would be above the carb base, on the lower to mid body of the carb itself.
In the Holleys and Edelbrocks I've had over the years, you would connect the distributor to the ported vacuum. Typically this would be above the carb base, on the lower to mid body of the carb itself.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,116
From: Crossville TN
The primary reason for the timed or ported vacuum connections is to retard distributor timing at idle for emissions reduction. As soon as you press the accelerator, it dist. can sees manifold vacuum and operates normally. But if your engine idle is much smoother with manifold vacuum, there's no reason [other than emissions] to leave it on ported vacuum.