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| | | | Joined: Apr 2005 Posts: 25 Apprentice | | Apprentice Joined: Apr 2005 Posts: 25 | I bought a 350 engine with a Holly carb to install in my 56 pick up. The carb has a vacume secondaries. I need vacume to power brake booster, 350 trans modulater,and vacume advance distributer.
There are 3/8 dia vacume ports in the runner of the manifold and in the carb base plate. There also is a 3/16 dia port in the metering block of the carb. A hose is attached from the area of the electric choke to the intake throat of the carb above the trottle plates. Can you tell me what hooks to what?
Thanks in advance | | | | | Joined: Dec 2006 Posts: 65 Wrench Fetcher | | Wrench Fetcher Joined: Dec 2006 Posts: 65 | The port on the metering block is ported vacume, the advance on the distributor connects to there. Any ports on the base plate are manifold vacume, the modulator and brake booster connect there.
Sean
doing what you love is happiness
loving what you do is freedom
| | | | | Joined: May 2005 Posts: 1,624 Shop Shark | | Shop Shark Joined: May 2005 Posts: 1,624 | There are vacuum ports above and below the venturi. This means one can have both high and low vacuum at idle and cruising rpm's.
Six volt guy living in a twelve volt world
| | | | | Joined: May 2005 Posts: 1,624 Shop Shark | | Shop Shark Joined: May 2005 Posts: 1,624 | I reread you post. My Holley does not have a vacuum hose attached to electric choke housing, so you must be looking at the distributor vacuum line like 1969c10 said.
Six volt guy living in a twelve volt world
| | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | Use a 3/8 outlet for the power brakes. The manifold one is best. Hook the modulator to a 1/4 in. tube in the lower part of the carb. The dist. hooks to the 3/16 tube on the side of the meterring block. The tube from the choke is to draw filtered air to the choke. It gets it,s vacuum through a passage in the carb.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | |
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