440-1 flow numbers

When I was there today, he said he won't even waste the electricity to flow a set of unported 440-1 heads because they are so bad out of the box. He dug through old files today clear back to the 90s. I can't remember the exact numbers from the one set of unported 440-1 heads he found flow numbers on (using the same bench), but they were very low. So low that I can't even remember the numbers lol. Tim has many years experience with flow benches and engine dynos. The flow bench he bought he used for many years at our machinist's shop.

We also looked at 572-13 heads that were CNC and he finish ported, wow those things are BAD A$$. I don't want to misspeak about the flow numbers he got from a 572-13 head, but it was substantially better (obviously) than my -1 heads. I want to say peak was around 420 cfm at .800 lift. No wonder they make such good power. He said they needed a good bit of work to get there. Every set of heads out of the box that enters his shop needs a good bit of work to make good power, even when they are CNC. He said that includes B1 heads, they are no better out of the box.

The heads I am referring to all had 2.20-2.250 intake valves. It seems like the 2.300 intake valves really picks up some power.

Thank you for sharing that info. It seems like the outlier heads are cnc and in addition hand ported to breach the 400cfm mark.

Of course there are people out there that claim 5,000,000 CFM from their Edelbrock RPM castings. Most of those combinations never make it to a track.

I think you need at least a 4.400" bore to go .800 net lift with a 2.30" intake.

All of my junk is 4.375" bore and 4.25/4.15" stroke.

I keep saying the last 400 block was my last stock block deal. Then I buy another 400 block.