I've just bought a 430 Buick, to replace my worn out 300. It's without carb. but i've got a brand new 4 barrel Holly 600 that i was planning to put on the 300. Wud the 600 be ok for 430 - or wud i be missing out on a lot of hp?? FYI the engine is stock, and i plan to keep it that way.

The stock Q-jet was 760 CFM. Let your conscience be your guide

I'm showing the following parts numbers in my Mitchell labor guide for this motor as being: 1967 #7035354, 1968 #7036530, 1969 #7036755. These listings are for an auto trans. If you need the manual numbers let me know.

how do you intend to use it? are you expecting a lot of WOT (wide open throttle) or high rpm use? if not you'll probably be fine.

i've been using a 650cfm holley 2 barrel on my 455 and it's been doing fine up to 5,000 rpm. i'm sure if i was to push 6,000 it would start to choke the motor pretty badly.

but then if you were going to be running 6k you ought to be having a pretty serious rebuild anyway.

http://www.holley.com/HiOctn/ProdLine/Products/FMS/FMSC/FMSC.html <<< Holley's CFM calculator page

I'm running a 780 holley double pumper. Motor is stock. The car runs great. Good luck.