Headlight Vacuum
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Racer
Joined: Oct 2013
Posts: 251
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From: SAN ANTONIO TX
Headlight Vacuum
I need the vacuum port that screws in to the back of the manifold of a 350. I have a few other items to complete before I can get it inspected and the headlights are one of them. First question is, Is it just a port or a vacuum switch like it shows for the 82? The ones shown have 3 ports. Is that correct? One for brakes, headlights and cruise? Next, Who has one in stock that doesn't charge arm and a leg for shipping? OR, has anyone purchased one locally? If so, Where? are the port sizes all 1/4" or is one 3/8 for the brake booster?
Thanks
Thanks
Melting Slicks
Joined: May 2015
Posts: 2,365
Likes: 428
From: Cape Girardeau Missouri
Yes, just a plain port into the intake manifold. In the factory system there is a filter and then a one-way valve with two outlets--one goes to the headlamp system and the other to HVAC. You must use a one-way valve unless you want the headlights to pop up and then down every time you start the engine and immediately loose stored vacuum when the engine stops. All of the vendors sell both the filter and one-way valve. While it's not difficult to get to be certain to test the one-way valve before installation just as you should do with all new vacuum parts.
I had to buy a new three-outlet port for my '79 about three years ago. I wasn't expensive but I've since heard that they are getting hard to find and dear in price.
I had to buy a new three-outlet port for my '79 about three years ago. I wasn't expensive but I've since heard that they are getting hard to find and dear in price.
1967 Pedal Car Champion
Joined: Mar 2020
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From: US-PNW
(Also catching my eye was the selection of water pump/manifold heater hose fittings that look just like the Corvette vendors' for 1/2 the price.)
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
Brake booster vacuum should be a separate (and larger) vacuum line coming from the base plate of the carburetor. (GM's booster supply was usually from the rear of the base plate.)
Last edited by 7T1vette; Jun 2, 2020 at 01:32 AM.
Is my vette stock?? HAHA
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You can pop up the headlights by climbing under the nose and sticking your arm up there and finding the springed part of the hinge. If you press up gently youwill find the pivot location and they will go up. Just have them up for the inspection, I had my wiper door tray open for my first inspection. They shouldnt be required to go up and down as long as you have high and low beam and they are aimed correctly
