Is Quadrajet better than Holley?

QuadraJet hands down. It’s not as easy to work on as the Holley but the throttle response for street driving and better gas mileage make it worth the effort. Plus there’s nothing like the sound of a Q-Jet at WOT.

Are Quadrajet carburetors any good?

The truth is, a properly tuned Quadrajet can be just as efficient and reliable as a bolt-on substitute performance carburetor. The Quadrajet has many model designations; the most adaptable units were designated as 4M, 4MC and 4MV, and most were rated at 750cfm until 1972 when their rating was increased to 800cfm.

Does Holley make a Quadrajet?

Holley’s products include carburetors, fuel pumps, fuel injection, intake manifolds, and much more. From start to finish, Holley has the parts to make your dream a reality….Features:

Barrels 4
Product Type Carburetor
Secondaries Vacuum
Supercharged Application No
Throttle Bore 1.375 inch

What CFM is a stock Quadrajet carb?

Quadrajets can range anywhere in between 600 and 800 CFM. Most are rated 750 CFM or higher. Quadrajets are used by many GM street car enthusiasts; however, they are also disliked by just about as many.

How does a Quadrajet carburetor work?

Quadrajet carburetors have mechanical secondary throttle plates operated by a progressive linkage; the primaries open before the secondaries, and use on-demand air valve plates above the secondary throttle plates. Thus, the Quadrajet acts like a vacuum-secondary carburetor and only delivers more fuel as it is needed.

Is a quadrajet worth rebuilding?

Yes, They Are Worth It. Each carburetor is inspected and assembled by one technician. Before any work can begin, the unit being rebuilt gets a thorough cleaning and inspection to ensure all parts are usable.

What can replace a Quadrajet?

Holley/MSD is thrilled to announce the release of Sniper EFI Systems for Quadrajet applications, which eliminate the need to continually rebuild 50-plus-year-old Quadrajet carburetors on classic Chevys, Pontiacs, Buicks, Oldsmobiles, and GMCs.

How do I know if my Quadrajet is 800 cfm?

When looking through the primaries, if you see a pronounced bulge protruding from the side of the wall surface, you have an 800 cfm carburetor. The primary wall of the 750 cfm unit does not have this bulge, and is consistent throughout. In the early ’80s, GM incorporated electronic connections to the Quadrajet.

What does Quadrajet mean?

The Quadrajet is a “spread bore” carburetor; the primary venturis are much smaller than the secondary venturis. By comparison, a “square bore” carburetor has primary and secondary venturis of similar size.

What kind of carburetor should I get for my Holley Quadrajet?

If you’re considering replacing an older Quadrajet with a new Holley, consider the 4165/4175 spread-bore line of carburetors that employ the same mounting flange and similar throttle bore sizes. If choosing a street-driven carburetor for the first time, it should be equipped with an electric choke.

Is the speadbore Holley a good carb?

My wife’s ’69 427 Corvette has a 650 cfm, speadbore Holley, Q-jet replacement carb. It’s been a great carb over the years and routinely turn out 17+ mpg’s. Plus it helps the BBC make a TON of torque throughout the range. I highly recommend one for any mild BBC.

Which is better a Holley or a Q-jet?

Q-jet or Holley, I don’t believe that one is any better than the other, one if just different than the other. There is really no way to compair them they use a different metering system. I prefer Holleys over the Q-jet, it is a personal preference. No way to tell you if your core is rebuildable, I am not sitting right ther with you.

What makes a dual inlet Holley carburetor different?

The dual inlet varieties just look more powerful. All Holley carburetors are differentiated by their capacity to flow air. This rating is expressed as airflow in cubic feet per minute (cfm). This is a measurement of the volume of air that passes through the carburetor as tested.