If yur looking for power, Here's your answer;
the formula is
(cid X rpm)/3450 x Ef= cfm
where Ef= engine efficiency
example;
(360 x 4400)/3450 x 70% =
459 x .70 = 321cfm
and this is at sealevel. The higher you go, the less air she will be able to grab.
By-um hey, it's only math;
Spend yur money on whatever, even tho, 95% of the time, a big 2bbl is all you're gunna need on a stocker.
But, you might ask, where did I get the 70% efficiency?
Well, I pulled out of a hat. It's a guess. Cuz stockers rarely even go to 70%. But, I'm a generous kindof guy, lol.
Listen it don't matter how big or how small a carb you put on her. As long as the carb is at least able to deliver 321, the engine will never draw more from a bigger carb. You can put 8 Single-bbls on her, each capable of 60 cfm, (total 480), but she'll never "pull" more than 40 thru each one. and that would be at 4400@sealevel.
so if yur loafing along at 3000, the maximum number of cfm available, is 220cfm. The factory 2bbl off a 318 can easily provide that,
never mind the factory 360 one.
Oh sure, guys will spend yur money for you, and you'll end up with a carb nearly twice as big as you need.
Tell you what,
Go drive your car, in Second gear, already floored at WOT; and time how long it takes to go from from 3000 to 4400, Repeat the test three times and write down the average.
Now go bolt on whatever carb you want, and repeat the test. How much quicker is it? Was it worth the money you spent?
I'm not a big fan of old-AFBs but if I had one already sitting on my stock 360, I sure as heck wouldn't swap it out. Your AFB Primaries are already almost big enough to get the job done.
But I get it, some guys just want to pimp out their rides a lil, lol. so have at it
