where to get vacuum
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Joined: Nov 2011
Posts: 95
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From: Indiana
where to get vacuum
I have a mildly built 68 327-Edelbrock Performer manifold- I have vacuum port from carb connected to PB booster-looking for another vacuum source for PVC system- I think I read at one time not to tee into PB booster line-without drilling and tapping manifold any ideas-port on manifold covered by carb. Thanks
Le Mans Master
Joined: Mar 2008
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From: Oxford MA-----You just lost the game!!!!
I have a similar setup-Edelbrock 2101 intake manifold with Holley 1850 600 cfm carb. There is really only one large vacuum source, at the passenger's side rear of the carb, and I'm using it for the PCV. there is a small vacuum source on the front of the carb, which I'm using for vac advance and shift modulator. Vacuum source for the headlight system is from the manifold. When I bought this car, the PO had drilled and tapped a hole in the driver's side of the manifold, and had a hose going to the power brake booster. It is still set up like this, and it works fine. ttoptom1 says he does not want to drill and tap, so that's out for him, but I wonder if he could use the manifold vacuum source for both headlights and brake booster.
Scott
Scott
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Joined: Nov 2011
Posts: 95
Likes: 6
From: Indiana
Scott, My carb vacuum is tee'd off to PB booster and vacuum canister which feeds headlights, etc. Small vac on front of carb to vac adv-Not against drilling and tapping-just didn't know of another source with my set up-
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
Power brake booster needs to be hooked to a large carb base fitting that is direct manifold vacuum. It should NOT be hooked together with the PCV fume-vent line (fuel/oil fumes could get into the brake booster). If you don't have another fitting, drill/tap the intake manifold to create one. Are you sure there's not a pipe plug located somewhere on that intake near the carb?
Thread Starter
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Joined: Nov 2011
Posts: 95
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From: Indiana
There is a tapped fitting on manifold but carb covers it-gonna go ahead and drill and tap another that is accessible-knew I didn't want to tie both lines together-Thanks for all suggestions
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
I have an Edelbrock 2101 with a Holley 600 on it, and yes, the rear bowl is above the drilled and tapped hole in the number 8 cylinder's runner, especially with a metering block in between the bowl and throttle body, like I have, but there is enough room beneath the carb to put a fitting in there. A carb spacer will help, I'll bet you can fit a 1/2" spacer under there. Easier than removing the intake and drilling holes in it, so it's worth a try.
Scott
Scott
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