cfm quadrajet?

[67_C-30]

Originally Posted by geezer#99

Just to clarify, you mean 1 7/32 primary Venturi and not primary throttle size.
Is that correct.

FWIW I thought the last 800 came from the 80 T/A with the 301 turbo. 750 cfm after that.

Yes, 1 7/32" throttle bore for the 800, 1 3/32" for the 750.

Most all truck Q-jets were 800 cfm in the 80's. I have a Q-jet from an '83 Z28 that is officially rated at 795 for some reason, but it is a 800 cfm carb.

[Ironangel]

Originally Posted by ronm69c10

i need to buy a new quadrajet to replace one that is cracked and old.I found an 800cfm quad at a good price.My question I have a stock 454 out of a p3o with headers.I have no ideal what was done during rebuild 5000 miles ago but motor seem's to be stock.numbers on bad carb. are 17080212. Is a 800cfm. a good choice. Also turbo350 trans,373 rear in truck. RON

An 800cfm Q-jet will work nicely on that 454 as will any 750cfm. The critical factor is in how they were set up and what they were set up for? Your going to want to get the number off the 800 and start your research, what year is it and what make of motor did it come off of etc. A Pontiac or Buick Quadrajet is set up differently than the big block Chevy Quadrajet. Using the information in the back of the GM Service Manual, you can gather specific information GM used in factory set ups. If you dont already have one, get one! https://www.ebay.com/itm/1972-Chevro....c100677.m4598 The 454 was not an option in our trucks until 73 but using the same jet/rod combination the 402 got should get you close enough. Heres a site Geezer turned me on to that is priceless in Q-jet trouble shooting and set up, http://www.digitalcorvettes.com/foru...ad.php?t=88376 And heres a forum that proved invaluable, especially with 800cfm identification and correct set up. https://cliffshighperformance.com/ I have both books and use them both. Cliff is a great guy and does great work, I can say that because I'm still running one of his Q-jets on my 408 BBC motor. He answered the phone when I called his number and when he found out what I was building he talked my ear off because he shares the same passion for these trucks. When he realized I had a punched out 1969 SS L34 396 this carb was going on, he said throw it in a box and I'll build it and tune it on my Camaro, that had the same L34 motor. Six weeks later I got it back and it's still running like a top! The Quadrajet in my opinion is the greatest carb out there. They give you better mileage than even a two barrel can if you stay off the pedal. No other factory carb has those 2-1/4" inch secondary's that plant you in the seat when you step on it. And you gotta love that unique roar when them secondary's open up....It's music only a Quaddy can play! And remember, "You can tune a piano, but you can't tuna fish" ~Ghostrider~