Found a set of #049 heads locally, the guy says heads have Manley street flow 2.30/1.88 valves installed with 11/32" stems. I heavent seen the heads yet but he said the runners have been cleaned up a little but not ported. Which kinda doesnt make sense with the huge 2.30 intake. He said he bought them done was going to use them then switched to SQ ports and used springs off them. I have 2 quetions. One, if they havent been "ported" (which my geuss is they have), How much better will the heads flow then stock 2.08/1.72 and 2.19/1.88. Two, will these heads be 2 much for a 454-468 with say a 235-245 duration and 600 or so lift cam with 10to1 compression. I can pick the heads up very reasonable $300-$350max. THANX

I bet they'd work great, TTT

I think one of the factors you have to look at is that you might have a higher incidence of valve shrouding if you bore isn't big enough.I think that with a .60 overbore you might be in spec.

In a fairly mild street big block, say up to 454 cubes, I'd much prefer the stock 2.06" x 1.72" valves. They will typically outrun "oversized" valves to 4000+ rpm, and especially in unported heads and a smaller than 4.25" cylinder bore! The valves are overkill if they're shrouded or the heads can't flow.

Steve

One thing you might need to consider (even though I think they would be a great head to build upon at a later date) is that those valves will more than likely sit higher on the seat so it will in effect create more compression.

How much? I'm not sure, but if the heads were good to begin with then they may have just barely cut the pockets for the newer valves and didn't recess them. An old trick to get more compession for race type motors.

Something to think about anyway.

Rob