Offshoreonly.com - Building 496 from 454, cam advice

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Quote:

Originally Posted by jeff1000man (Post 2892985)

The squatres are only better with more displacement or cams. In marine engines the big chevy or Merlin ovals are etter except for maybe that last few rpms up close to 6000. Ask around on the board. Those ovals are better overall in the middle and down low, and they don't cost enough horsepower up top to make a difference.

If you are going with the squares, you might want to stay with a dual plane to help in the mid range. 500hp is not a very hard number to reach with that engine, but remember you are going to get way better torque numbers with that 4.25 crank then you are with that 4" crank and that is what you want.

Here is an oval port head that is the ****z.
http://www.sonnysracingengines.com/c...max-flow-heads

OK---it's abit pricey. Oval or square, it's about your combination of other components. Give RMbuilder an email or PM. Bob knows marine motors. He can also design a cam for YOUR combination. No cookie cutter crap.

RMBuilder/Bob Madara of Marine Kinetics in N.Y. is the man with the cam.......the cam guru and will get you the right cam for YOUR application and what you want to do with it. 585-654-8583

can I get away with 10:1 compression if I use a big roller cam from Bob Madara, iron heads, I'll only use 93 octane? I will eventually get alum heads, but in the meantime they are not in the budget.

The only way I would run that compression is with aluminum heads. On the street it would be fine however as you know in a boat the engine is under a constant load. Kind of like driving a be heavy truck up a steep hill for hours at a time. I would go no more than 9.5 to one. Perhaps use a thicker head gasket with your iron heads and then a thinner one with the alum. Just a thought.
John

Quote:

Originally Posted by redstinger (Post 2916875)

can I get away with 10:1 compression if I use a big roller cam from Bob Madara, iron heads, I'll only use 93 octane? I will eventually get alum heads, but in the meantime they are not in the budget.

If you are serious about doing somthing and ready to spend some money, call Bob Mandera before you buy ANY parts. I just gained 5MPH from a roller cam and matching components. Of course if you are not looking to go fast just buy the generic parts off the shelf.

Try calling morgan & son racing engines @ 972-264-6977
they deal in all engines from stock to 800ci and above mostly drag racing but he is the best engine builder in texas