Plenum effects on induction.

[powerband]

As discussion I was thinking of the the Offy type modification of 3 intake port - OEM center and cyl's 1/2 - 5/6 bored ports on the intake runner.

> A simple plenum box "adapter" from 4Bbl flange to the Offy' three carb ports? .

> IF instead of three single carbs, a plenum box to the 3 ports arrangement with (say) a single moderate 2or4Bbl would have what general effects on engine operation ?.

( I am considering experimenting with an alternate to the Offy 3X1 I'm currently running (250 bored to 260). Current 3X1 Offy' with outers blocked and center fed with 2X1 adapter and Holley 350 CFM ran quite well.)





have fub

 

[country fried 6]

i would think that a large open plenum like that would cause fuel to drop out at low rpm operation, also throttle responce would be sluggish. i might work out in an aplication that sees WOT for extended periods, but then wouldn't you want the 3 carb setup?