My old heads had the standard size valves, (2.25/1.94) and after some work on them flowed 386.2cfm@.800@28" on the intake and 230.1@.800 on the exhaust. The motor made 853hp&818ftlbs. with these heads on my dyno. I had the new HiPo's flowed, they feature 2.40/1.94 valves. The intake flowed 443cfm(corrected)@28" and the exhaust flowed 255cfm(corrected)@ .700 ( the guy didn't know my cam was as big as it is so the numbers are probably a bit low). These heads are as delivered with no porting. It will be interesting to see what numbers come up on the dyno. Dave

Sure will with that jump in flow... were your
other head flows corrected

Mike I'm guessing they were, Jeff at Modern flowed the old set. It would have been fun to see the numbers at .800 too but I didn't want to bother the guy. He's very busy all the time and he's 73-74 years old, he can get real particular on what he works on.Dave

What are Indy HIPO heads? I,ve heard of Indy SRs ,-1's and 572-13 and 600-13's?
Mike

Hemi! These are the old Canfield Heads Indy now makes, and they are a pretty decent price. I run a set of them on my Hemi....

Why would the size of your cam affect the flow numbers?

.
What I meant was I'd liked to see the numbers at .800 also, my cam is .767 lift on the intake. Sorry for the confusion. Dave

The Hi-po head is the same casting as the 426sr right? Couldnt a guy just open up the intake valve on the sr's instead of buying new heads altogether?

The hi po head has a 66cc larger intake runner and has the ex valve moved/rolled slightly to accommodate the 2.40 intake valve.

The Victor head splits the difference between the SR and hi po, it's 245cc with a 2.32 intake valve and flows a touch over 400cfm ootb.

They are a slightly different casting, when you look at them side by side you can easily see the difference, more material heavier castings. The exhaust port is raised 1/2", material added at the intake face, drilled for 16 bolt manifold and also a 6 bolt manifold.
The raw numbers for the intake port are;
.100-85, .200-171, .300-256, .400-333, .500-406, .600-429, .700-452, corrected at .700-443. Dave

What does your motor make now, and what are you hoping for with the new heads?

DuWayne, 853hp&818ftlbs.now. It should push it past 900 with ease.

No, the bigger valves would hit. These have the exhaust valve rotated so that they will clear the larger intake valves....

Dave, what were your old heads? Also Indy...??