Long valves on W2's with .600 lift?

Well I got to the shop today to pickup my W2 head. Here's the flow #'s.


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The intake stalled at 294 cfm...the exhaust at 230 cfm. Used clay on the intake for a radius and a short, curved pipe on the exhaust.

All things considered I'm OK with those numbers. Porters I have spoken with say they need to square off the ports and really dig to get 310-320 cfm out of these heads. Then I recently read a tech article that discussed taking iron square port BBC heads and getting better flow when they OVAL the ports. Oh boy...

When discussing flow and lift a few years ago with Mike Jones @ Jones Cams he suggested a cam with a .565 lift as I recall. This morning Mike S., who flowed my head, told me to stay at .600 or less. Said .565-.570 is what he'd recommend. After so many years of just using a cam based on experience and a recommendation or two I can see where I used a bunch of them that were way too big for the heads I ran.

I recall using a .600 lift/[email protected] cam in my 351C 2V heads. I know for sure those were 50 CFM shy of these W-2's.

What's odd, or maybe not odd, I know guys running Brodix spec heads (SBC) that flow less than what I have and they are running lifts in the .650 to .700 range. 650 HP-ish. Maybe that's why they aren't fast enough to break away from the pack... don't know.