Buick 350 Carb Help

[J-Man]

I am in the process of building a mild 72' 350. I need help with my choice of carb to go with it. As of right now I wanted to stick with the Quadrajet to keep the Buick looking more original plus from what I read there is plenty of performance and reliability with these carbs. Here is my build to help with what I am looking at:
~block is bored .40 over
~comp is 9.6:1
~heads have a mild port job with gasket match
~TA aluminum dual plane intake
~camp cam 92-203-4 (ad. in: 268 ex: 268, @.50" in: 218 ex: 218 Valve life is at .469
~Headers with dual exhaust
~automatic transmission
~power brakes, power steering
~a/c car

I have been told a '73 455 carb that is re-jetted will work just fine in my build but I want to make sure before I put the money into the rebuild. I know the 455 carbs are 800cfm and the 350s are 750cfm. Should I go with a rebuilt 350 carb or the 455 carb that is re-jetted and tuned for my 350.

Thanks for your help,
Jake

[clanceman427]

id stick with the stock 350 carb. i believe the 71's were 800 cfm

[carmantx]

Hi Jake.
in my opinion, you are better off with your build to work from the Buick 350 Quadrajet. Anywhere from 70-74 for divorced choke or 75-76 year if you wanted electric choke. These carbs are rated at up to 750 cfm, meaning if set up correctly with baseplate throttle blades opening to 90 degree and secondary air flaps set correct.

the 455 Quadrajet from 71-76 do flow 800, but there are many differences in the circuits that require quite a bit of work to set it up correctly. Much easier to modify the 350 carb for the added modifications.

[carmantx]

Forgot to add, if you are doing this yourself, make sure you get your parts from cliffshighperformance.com

original jets were 68 and you can go up a size and replace the primary rods. You will also need to open the air/idle circuits so it will idle correctly with your cam.

if you aren't doing it yourself, please consider my services from quadrajetpower.com

[J-Man]

Thanks for everyone's help. I have a 73 455 carb so I guess I will have to weight out the odds of getting a 350 carb or not.

Jake