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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Why Quadrajet's are awesome part 1

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.

How to debog your Quadrajet part 3
In the first two videos we looked at operational theory of the Quadrajet. In this episode we'll explore a couple mistakes the home mechanic often makes in an effort to improve the performance of this unit.

Identifying Quadrajet vacuum ports
I always see a lot of questions about what various vacuum ports do on a Quadrajet. Here's a general guide that will point you in the right direction. Remember that there were many different Qjets over the years and vacuum port locations and number will vary. This video is representative of 1975-90 carbs. Enjoy!