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I bet it would work great I wa using a cam with .625 lift and it made peak hp at 5650 rpm

Quote:

Originally Posted by Ms PatriYacht (Post 2395167)

Afr 315 cnc but get a custom cam. The 525 cam is actually a little big for that combination. 550 hp with excellent drivability will be easy with that. Dammit Donna was logged on, Ian

I was readin along thinkin DAYUM this lady knows her **** :D

Quote:

Originally Posted by mrhorsepower1 (Post 2397616)

I personally like the Dart components. They flow better across the range. AFR flow numbers are inflated . I have personally flow tested many sets of heads on our 600 Superflow , and the number do not jive to what they really are. If your looking at price the Dart Iron Eagles are no doubt the way to go. They also have an alum. version which is 310 runner. Everyone has their preference. I also sell and use alot of Brodix Heads. Depending on application, one of these two companies will have a perfect match for what your looking to do. As we all know here, it's knowing what combinations work the best that will make the difference between bolting on 40 horsepower or gaining 100 HP.

Thanks Randy. Now that's what I call priceless information.
Speaking strickly heads, I am so tired of hearing HP this, Torque this. All are meaningless. Put the head on a Flow Bench and read the results. Sure would be nice to have an across the board (manufacturer of BBC head wise) comparison of first cast iron heads, then aluminum heads. Each classed in their respective valve and runner sizes. Sorta like a Consumer Reports of BBC marine heads.

Do internet search cyl head flow test, its an AFR site has flow test of 16 heads alum and cast , same bench and test equiptment found it one day playing. hope it helps Randy

Quote:

Originally Posted by IRONMAN (Post 2400230)

Would the AFR ported 315 work well on a 598 at 5600 rpm? It looks like it will flow enough in the .6 to .65 lift range.

I remember asking RMBuilder the same question a year or two ago---he said it was somewhere between 5000-5500rpm, but I cannot remember the exact RPM he stated before the intake air flow would go into turbulence for an engine that size (598cid) with the AFR 315 CNC ported heads. Even so, 315cc's would be cutting it a little too close for me. I would opt for the next size up from there---the AFR 335 CNC ported head for 598 cubes. Perhaps someone else can chime in, but I would still put a call into RMBuilder/Bob Madara of Marine Kinetics and see what he says.

Ok....new scenario.....I have the chance to purchase a 530 HP motor complete, with 140-150 hours from a very reliable source. HP500 injection setup, remapped ECM. Dyno sheets show 531 HP. Is a volvo setup, my next question is are the wiring harnesses compatible?

I may end up keeping the 509 bottom end and doing another motor, possibly for a car or truck. Decisions Decisions!! Thanks for all the info.:D

Is it factory stock? You would need to go through the top end mininally. Hopefully this would be equipt with the eickert headers. If not, I don't see much benefit over building what you have.

another thing to keep in mind with the dart heads are you need to get longer bolts to secure to the block as i learned with my motors

It doesn't have Eickerts on it Dave. Imco powerflow. The person who has the motor is very knowledgeable and a trusted friend. But I am still looking into building up the 509 if $$ allows.:D

Quote:

Originally Posted by R Addiction (Post 2417710)

the 500 dpx volvo motors had the same cannon plug connector as the mercruiser ones if that is the motor you are looking at