Im wanting to run multi carbs, and i know this isnt the awesome way to do it but i dont want to spend a fortune in finding a vintage intake, buying carbs, linkage, etc. So im thinking bout the 2 and 3 carb adapters made out there to bolt to a 4barrel modern intake. I have a 402 Big Chevy, bored .060 over, mild cam, RPM Air Gap intake, and 3310 Holley 750 on it now. Did have a 650 holley on it before i swapped to the 750. Ran good with the 600/650 cfm carb too. Ive been looking at vintage speed's website and reading, but dont believe the claims made by them on the cfm ratings of their setups. almost 600 cfm on a 2 carb setup, and 900cfm on a 3 carb setup. My question is i have no experience / knowledge of 2barrels. I just like the look.(Typical young guy huh) I dont know what cfm ratings all the styles of 2bbl carbs have. Anybody have any info/ could shed some light on what i need or could use? Anyone have any experience using these style of multi carb adapters? I did search and read some bad posts about Charlie at vintage speed, but that was 5 years ago or so the threads were dated. Any help is appreciated.
I wouldnt be screwing it up, Could always switch back to my good 3310 Holley 4barrel. I simply like the look of hot rods with multi carbs. Nothing more cooler than multi carbs. Except well, a blower and multi carbs. But my motor wont handle boost.
CFM for 2 barrels are measured at a different vacuum then 4 barrels. That's where the difference is probably coming from. For example the "500" CFM large base 2GC's flow about 350 CFM. Do a search and you'll find the exact formula.
I saw a thread all about cfm rate/calculations. Difference of 4barrels being calculated at 1.5 inches of mercury and 2 barrels at 3 inches of mercury i think. I attempted to read it and got seriously lost, i would have to study it for a while. Link to that thread- http://www.jalopyjournal.com/forum/showthread.php?t=169625 edit- i read it again, i think i see what is meant. The newer 4barrel carbs only require 1.5" of mercury "depression level" as the older 2 barrels had to have 3" of mercury (flow-bad term im sure) to work properly.
The Jalopy Journal
