Buick Q Jet Carbs, 750 and 800 CFM Questions
 

I've read q jet carbs up to 1970 were all 750 cfm. Including 455 engines. Starting in 71 they were all 800cfm. Is this true?
I have 2 carbs a 1970 factory replacement for a GS350 7042944 KH 0032 and a 1973 7043240 LA 0253 oem from an electra.
Looking to use the better model of the 2 on a 455. Not stock eliminator, street resto of moms old Buick.
Thanks, Chris.

Re: Buick Q Jet Carbs, 750 and 800 CFM Questions
 

If the Electra was a 455 it probably has the higher cfm carb . The difference is on the primary side diameter around the venturi. Look into the throats of both carbs there is a noticeable bump in the casting adjacent to the idle speed screw.---Trevor

Re: Buick Q Jet Carbs, 750 and 800 CFM Questions
 

I did last night at my engine builders shop. Then went home to confirm my eyes findings on NHRA Blueprint guide. Definitely a difference in size, and booster styles. 73 it is, w new bushings and float. Thank you for confirming my findings.
Chris O'Keefe.