which heads for a 408ci?

It's an approximate paper calculation of what it takes to push a 3100 pound car to a 127 mph trap speed. It works out to 596 flywheel HP. Granted it's not as accurate as an engine dyno but it's close enough for what we do.

As for RPM's I twist it to 7200, it still pulls to 7500 but since the bottom end is pretty much stock (it's a MP crate short block) I try to keep the RPM's down.

I can tell you the heads flow 300 cfm's @ .600 lift and 305 @ .650. With the 1.6 rockers the gross lift is .672, minus the valve lash the actual valve lift nets out at .650. This is enough flow to support 600 ponies but since the short block is nothing trick I'd assume it suffers a little there.

As for the torque? Who knows. It leaves harder than my 340 did but doesn't run as strong at the top end. The 340 (spinning to 8000 RPM's) was a real top end charger.

The car runs virtually the same with the 360 as it did with the 340, within .02.