A friend brought over a carb that is said to be a 800 and looking at page 109 of doug roes book there is a small hump inside the primary on the 800. And the 750 has a ridge all the way around. This carb has the ridge all the way around but he clains it is a 800. He said it has the 1-7/32 throttle bore.????
What is the carb #? All Q-jets have 1 3/8" primary throttle bores. The 800's have 1 7/32" diameter large venturis. The bump in the picture is the tip off. All 800's went on 455's from 71-74
Guys, The picture is worth 1000 words. So is the book from Doug Roe. I have "lost" two copies of the book, and have replaced it within a week, as soon as I could locate a copy. It is my understanding, though that the carb pictured is an 830. This is picking nits, but I have a question along these lines. Edelbrocks ads cover the carb as using the original tooling and molds. Yet their ads also speak of a 795 cfm unit. My recollection when going to school from GM was that these carbs were either 750's or 830's. What do you think? Ray
Ray, The only difference that I know about is the size of the large venturi. It is 1 3/32" on the 750 CFM, and 1 7/32" for the 800 CFM. Maybe they are rating them in a different way. Aren't they reated at a specific vacuum level?