750 vs. 800cfm Rochester Quadrajets-how to tell them apart

There exists a ton of misinformation regarding the actual airflow capacity of the Rochester Quadrajet. Not many people know how many variations there are or how to tell them apart. Here is a simple video explaining how to identify each size based on casting design. I will cover the "cfm-limited" carbs in a separate video.

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Let's look at a factory high-performance Quadrajet
These late 70's Pontiac Quadrajets are probably the best of the post-1975 "modified" Qjets. They were originally installed on 77-79 Pontiac 400 engines. Fairly rare.





#3 Quadrajet main body--Kickin' Holley Butt
Google the #s on your QJ. If GM put it on an engine of a different size than what you are going to use it on, then you need to recalibrate it. Watch and learn.





Rochester Carburetor Trick!
If your Rochester Quadrajet or Dualjet Carburetor is Hesitating try this Trick!





Decoding a Rochester Quadrajet part 2: Breaking down the numbers
In this clip we'll learn how to decipher the Identification number and julian date code on the Rochester Quadrajet.




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