Offshoreonly.com - Promaxx 320 flow numbers

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Quote:

Originally Posted by adk61 (Post 4524857)

[ATTACH=CONFIG]564296[/ATTACH][ATTACH=CONFIG]564297[/ATTACH]

AKRacing/Promaxx 317s... Intake .200 = 155cfm, .300 = 228, .400 = 289, .500 = 336, .600 = 368, .700 = 388 .800 = 392 exh .200 = 117, .300 = 158, .400 = 205, .500 = 228, .600 = 258 (w pipe 277) .700 = 260, (280) .800 = 261 (283)... so this is preliminary done after minor bowl work and marine valve job...

So I ordered a set of these today. Other than the heads I believe my build has been done several times before so we shall see what it makes. More than likely I will dyno at Brian's when its together.

Talked with Jim V this morning about these heads, the castings look great and after he flowed them outta the box the intake were comparable to dart 320's but the exhaust is smaller and can be ported or machined for whatever your engine setup is. Tell you what at about 1k shipped for these bare seems like a great budget head.... Kinda replaces the Patriot heads since they went out of business.

Quote:

Originally Posted by rjewell1988 (Post 4525635)

agreed, the exhaust has plenty of room to grow, we've been doing some testing up here in the snowy north lol, and these Promaxx heads offer a solid base for the buck... the intake side shows to be a bit better than the Dart 320, but the head really comes alive with some bowl work and a massaged valve job,
again... great bang for the buck, and in today's economic times I think we all need a break!!

Quote:

Originally Posted by phragle (Post 4525615)

So I ordered a set of these today. Other than the heads I believe my build has been done several times before so we shall see what it makes. More than likely I will dyno at Brian's when its together.

Thanks Rob... I'm sure you'll be pleased!!

Anyone weight them against a dart or afr casting?

Quote:

Originally Posted by Full Force (Post 4525678)

Anyone weight them against a dart or afr casting?

Well there's the QOD... :lolhit:

Quote:

Originally Posted by cigrocket (Post 4523447)

So did we get some flow numbers for the final porting? I was wondering how they compared to the CNC version that Promaxx offers. I was wondering if the CNC version would actually be cheaper in the long run because less hand porting and cleanup would have to be done which would save in labor costs. Just wanted to know the flow on these bare heads. I am looking at possibly buying some sets in the future.

Kurt, IMPO I think the CNC version of these heads would be too much head for your combination and the goal you strive to meet... as we discussed in various conversations, the 360+ CFM @ .600 lift on intake side is a great fit and will accommodate you at both WOT and when cruising...

Keep your eye on the ball buddy, ya don't wanna overbuild this to the point that you sacrifice the normal operation of the boat!! Unless, of coarse, you changed your mind and decided you're goin after the shootout!! LOL

I will work on a specific setup customized to your application, My version of the Promaxx head will do what you want and then some!! Feel free to call on me if you have questions,
Thank you

Quote:

Originally Posted by adk61 (Post 4525685)

Well there's the QOD... :lolhit:

So why is that a stupid question? Wtf?

Quote:

Originally Posted by Full Force (Post 4525695)

So why is that a stupid question? Wtf?

It's not at all a stupid question, I just feel kinda stupid that I never even considered it as a viable thing to check!!

and I'm just trying to maintain a little levity here too!! lol :thankyouthankyou: