Kinda curious about that myself. Lol.... I do know currently Jim v. Is at or near 340 cc on the intakes but the floors aren't welded up yet. I could have Jim skip the floors but there's a lot of power to be made there. Honestly I would expect to be up near a cnc'd head with all the good guy parts when said and done but again the time going into these is well above the normal port job and clean up work.

Jim mentioned the time invested would be no different than any other after market heads. So in s nutshell if I woulda went with dart or afr the bottom line is the job would be the different by the cost of the initial non cnc'd head but I know exactly what will be bolting on and not have to check anything. I would imagine one would save a lot with minimal port and clean up work and assembled with the right parts.

The only issue I see is if you ever sell someone may want a name brand head, personally if they are good they are good, who cares the name...

I can say one thing for sure, they are good, as my name only goes on a good product and jointly, Promaxx is represented as their name is riding on it as well...

In no way will I belittle their product by excluding their efforts in developing a sold platform from which we customised it to meet our specific needs...

Is Promaxx anyway tied into what used to be Patriot Heads?? And what ever happened to Patriot they used to be a good head as well at a good cast that was cast in china

Patriot went out of business likely due to poor financial management as well as other issues... New owners bought the facility and redesigned the head creating what is now Promaxx... so "tied to" I suppose one could loosely make that reference, however one company really has nothing to do with the other...

Hope that helps...

Answers my question 100% thanks.

The AK Racing/Promaxx version is a reworked Promaxx 317 targeted to meet the needs of the marine high performance industry

The AK Racing/Promaxx marine head:
[ATTACH=CONFIG]564538[/ATTACH][ATTACH=CONFIG]564539[/ATTACH][ATTACH=CONFIG]564540[/ATTACH][ATTACH=CONFIG]564541[/ATTACH]
Fully blended intake bowls from the seat through to the transition
Reconstructed venturi intake and exhaust
Marine valve job with wider seats for better cooling of valves
2.250 or 2.300 Severe Duty intake values
1.900 Inconel exhaust valves with fully polished ports for optimal flow...
High quality endurance valvetrain...
Each head is assembled to the end users' application and then vacuum checked to ensure proper valve seal...

Sounds like a win win situation! Good product at a tad less cost.

Also available in CNC versions 340 and 370... they flow big numbers for a 23/4* head