From Bob M on my 540 build that I am looking at AFR325's through him.....cams and valvetrain also..

"spend the extra 175.00 on CNC combustion chamber porting while buying the heads now, full port not needed in your application at 700hp" he said on a combustion chamber CNC cleanup is 80% of the gains over a full CNC job, now we did not discuss gains in actual HP over not doing it, but I know that since I am buying heads and they will be new, I am gonna spend that 175 per set, lets say it is only 25HP, thats a very good return for 175.00 in my thought process....700.00 more for full portthat is not needed in my application he said is not worth that 20% Again, that is MY application and Dales goals are nearly Identical to mine.

Yes I have. Porting heads makes a huge difference, My first set was in the early nineties David Reher did a set of GM w port heads for a 496cu in top sportsman engine. holley tunnel with twin dominators, it made just shy of 1100 hp. not only did they cnc port the heads and combustion chambers but they also cnc matched the pistons. My latest ones were 2 sets done by Curtis Boggs, they were done from a program designed by Island Racing. The castings they used were Brodix -2plus mainly because these had enough material so they could get the design they wanted. These are 565 cu in. 9.3 comp., efi's. Tim Hogan made us a set of sheetmetal intakes and we use hardin cyclone headers. They made just over 750 hp fully dressed running wet exhaust. more important is the nice long flat torque curve, at 3500 rpm they are making 560 ft lbs. with a peak at 5300 at 685 ft lbs, and at 6400 where they make peak hp they still make 620 ft lbs. So yes cnc porting is well worth the effort if you take the time to plan the whole engine. We spent 3 months working with Tim to get the intake runners and plenum design right so we could acheave the torque curve we were looking for.

Single 4 on the 565's

No a merc 525 mono blade that was cnc much larger not sure of the cfm of it though.

Oh sorry didn't catch the efi. Even though I read it twice.

CNC in of itself means nothing power wise.

It's all dependend of what your motor wants, what it's getting now and what that head with whomever's port that's been copied into the cnc programming, will get you.

Since this thread started with a very generic question, I'll go to an extreme.

Buy a set of Edelbrock Pro Ports, finish the comb chamber and valve seats so you can put valves and valvetrain on it and go run it. It will be a turd cause everything is air orifice is puny, leaving as much metal as possible so the head porter can make port out his own runner design within reasons.

So, say on a 540 10:1 motor this could be worth several hundred horsepower or more.

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Anybody here could 'port' a set of heads and send them in to be digitalized and thus have a cnc machine for heads recreate those in other same heads whenevr you want.

Chances are, most of us won't want them.

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Many of Brodix's heads are not that great out of the box. Why ? Same concept as 'Pro Ports' Because they realize most will go to a head porter before it get's put on an engine. Thus, these heads will concentrate on leaving more material for the porter to be able to do more of what they want to do .

Furthermore, thus why Brodix get's more 'bad mouthed' by the bolt on and go crowd, vs the very serious crowd.

You need to call a cylinder head porter tell him the castings you have and see if you will benefit from the work. Call more than one porter.
My NA engines make 960hp@6700 with no superchargers. 900hp@ 5800 840lbs@5200

I am a die hard Brodix guy they make big power out of the box. Stronger rocker bosses. The dart rocker bosses are not that nice.

On the pro 1's yes they aren't the best. But the Race Series is a different story. Did you make 960 with Head Hunters? If I had the money Id give the SR20's a shot I bet it would be a killer head on a NA marine engine. I bet they would go 1050 on pump gas.

X 2 on the Brodix