Mike, Found this. Relative build to what you have going on. 454 with AFR 265's and crane hyd roller

http://www.hotrod.com/articles/crane-cams-dyno/

I bought a set of flat tappet crower edms for a Pontiac a few years ago and one of them looked like bottom was finished with a 36 grit air sander and I think one was missing edm hole, their QC inspector has to be blind and retarded.

Hey Mike, I did a Mk IV 454 jet boat engine a few years ago with the 741, AFR 325 cnc chamber heads, single plane intake,9:1 compression and 850 carb. It pulled a solid 600 HP at 6000 RPM on the dyno(didn't pull it past 6000). So I would think you would be just about the same.

Bob

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[QUOTE=mike tkach;4524876]after doing some research i decided to go with a crane 168741 cam.in this small 462 cu in engine i think it will pull hard to 6400 or so and still have more low end grunt than the car can use]

that,s good to know bob,i think it is going to have a nice power curve with the 265s.just wondering why you went with the 325s.

So who won ? I don't feel like doing the math to see who was closest ? And what's the prize ?

looks like you are the winner,pm me your address and the prize will be in the mail.

2 others were also close so i guess the prize get,s split up three ways.

Figured you'd have that question...LOL Remember a jet boat only has about a 1000 rpm operating range at WOT, so low end doesn't matter at all. It was also about availability at the time. I personally don't think a smaller head would have made more HP, but definitely a much better torque curve. I sure hope to see a dyno run with those 265 heads though!

Bob

the owner is willing to spring for a dyno session but the place that has done my machine work&dyno time is having some issues and i am not sure where to go for a dyno day.