4150 Holley
Thread Starter
Le Mans Master
Joined: Apr 2000
Posts: 5,202
Likes: 10
From: cincinnati ohio
St. Jude Donor '09
4150 Holley
I have a like new Holley 4150, 4776 600 cfm mechanical secondary carb that has no ported vacuum outlets. Does anyone know if this was common with older Holleys :confused:
Le Mans Master
Joined: Mar 1999
Posts: 6,744
Likes: 1
From: delmont pa
Cruise-In I Veteran
Cruise-In II Veteran
Re: 4150 Holley (yellow 72)
holley race carbs(double pumpers) had no need for vacuum advance ports. with some careful drilling you can add it to your carb. just check out a carb with it and copy it.:chevy
Safety Car
Joined: Feb 1999
Posts: 3,631
Likes: 14
From: Fountain Hills AZ
Re: 4150 Holley (yellow 72)
Early carbs (Holley or others) didn't have a ported source. If yours doesn't, it's a safe bet that it doesn't have power valve protection either and you might want to add that also. On the later Holley's that have a ported outlet, it's on the passenger side of the metering block above the idle mixture screw.
Thread Starter
Le Mans Master
Joined: Apr 2000
Posts: 5,202
Likes: 10
From: cincinnati ohio
St. Jude Donor '09
Re: 4150 Holley (Vetterodder)
Yep, Vetterodder you're right on it. I talked with a Holley tech and he said that the original 4776 carbs were not set up for ported vacuum and have different main bodies and throttle plates. :cheers:
