I ran the big valve version of the aluminium head on my Stroker way back when. That head (.202/.194) is no longer avalable as it cam directly from Patriot Performance who is the shop that actually makes the head.
It was a night and day difference according to the but-dyno...
The currently available head, from Hesco, uses stock valves ( 1.91/1.50) so the advantage is combustion chamber temps being controlled better and the redesign of the chamber itself. In the past, I have spoken with Bernie many times and he is a very good source of information.
I suppose, given that the castings were the same, a guy could have a competent machine shop open up the valves to take the chevy parts...
The other nice thing about this head is that the valve cover mount is raised 0.500" to allow roller rockers to fit. That and the T-Stat location is forward to allow fitment.
I nice head, but it is nearly twice what I paid for the big valve version back in '02... Makes for very expensive gains as you could spend less with a shop on the iron head and get similar results. For $2k, a full porting job, including raising the floors can be had along with a three angle valve setup.
They are pretty though...
A lot of old school muscle cars run flat tappet cams even some modern v8 performance crate engines. Roller is better, but flat tappet is no slouch either.
