That intake was generally set up using the 390 Holley if you wanted to run a four bbl. It’s the one I used when I ran that intake. You have to tinker a bit to get it dialed in. The other option is the 450 Holley. I am not sure they still sell that one, they use to sell it as a ford replacement. The 600 is a possibility, but the others are right, you would want to use that carb on a very high performance motor, really race motor.
I run 2 350 Holley two bbl on my 261 which rated at the 1.5 4 bbl rating comes out at 245 cfm or so per carb, so about 490 cfm measured at 1.5 hg. It’s a pretty modified motor and runs pretty well on that set up, even from idle. So for a mild motor, 600 is likely too big.
Now, there is an alternative. Clifford sells a two bbl adapter and you could run a single 350 two bbl. Would be about 250 in a four bbl. A 500 Holley 2bbl would likely also work, as that carb works out to about 350 in a four bbl so would be in the range.
Last edited by Dragsix; 03/07/2022 3:18 PM.
