Highest flowing sbm heads?

B3422w5 said
Jerry Arnold( you may not have heard of him, but national record holder in comp eliminator, extremely respected head porter, yada, yada…Rest in peace)….had a P7 head on his bench a few years back…busted 400 cfm… he was amazed by how nice those heads are.
I have heard several high end guys say it has more potential than any other small block head.
I suspect the fact the R5 was such a short decked creature, and nothing else existed to bolt it to( until now with a Ritter block) that the likely hood of people throwing together a big inch P7 combo kinda passed the market by.
Don’t know of any such efforts undertaken, maybe Kent Ritter would know

I could be mistaken but there was a black altered at Norwalk a few years ago running this combo (P7) several years ago. My son pointed him out to me. We talked in the lanes and he told me all the stuff he made and manufactured for it. That engine lacked torque but man did it love rpm. It had a totally different sound to it from the water box out. It may have been one of the other Nascar engines as it’s been years. Probably around the time the big block Mopar TrickFlow heads came out.