Hello, I am new here and from what I have seen it looks like a great site.
Does anyone know the specs on an 89 OMC 350 King Cobra engine? Did this engine come with forged or cast pistons and crankshaft?
What was the cam specs for this motor?
I am assuming it is a 4 bolt main block and the original brochure that came with the 89 Four Winns Liberator 201 I just bought says it has 270 horsepower and 9.3:1 compression but that is all the info I can find on this motor.
How does this engine compare with the Mercruiser 350 Magnum?
I have had it up to 50 MPH on a choppy lake with 3 adults and a child on board with between 1/2-3/4 of a tank of gas, what are some more basic things that can be done to pick up some more speed with the Liberator 201?
Thanks
Rob

I think they used the same GM engine as the merc magnum 350...thinking they used all cast pieces, just a basic 350 with a different cam and better intake..going to vortec heads and performer RPM airgap with a decent marine cam will get you the most bang for the buck..until you want to go thru the complete engine..then look at making it a 383 with the above heads...Rob

Thanks for the reply ezstriper, I thought the Mercruiser 350Magnum had the forged crank and pistons but was not sure about the OMC King Cobra 350.
I am thinking about building a 400 small block I have sitting in a building behind the house, any thoughts or suggestions on a combo for the 400?
I have a set of Corvette aluminum heads on it that have been pocket ported and flow very well for what they are, they outflow the stock vortec heads but not sure about using them because of the 58cc chambers. I dont want to get into a situation with to much compression and need to run expensive gas.
Thanks

what are you going to do about the hub on the flywheel, your 89 is a one piece rear main seal motor and has a smaller hub on crank verse the older 400 that has a larger hub because its a two piece main seal crank set up.

I am new to boats but I thought that you used the manual flywheel for the 400 and the power coupler bolted to the flywheel.
Does it make a difference that one motor is a 1 piece rear main the the 2nd is a 2 piece rear main if I use the correct flywheel for that engine?

That should work

I've been running a 400 sbc for a few years on a cobra drive.for the 400 you will need either a counterweighted flywheel or have your machinest drill the flywheel to counterweight it and also dowel the flywheel /flange to match balance.( what I did) also the one piece seal crank has a smaller diameter bolt circle. find a coupler from a earlier 2-piece seal crank. I ordered mine from OMC dealer. (now volvo) probably can find used.

P.S. the 58cc heads are going to really bump up your compression with a 4.125 bore also a lot overhang in cylinder. and you will need the steam holes drilled in heads. I also don't think the deck thickness on the aluminum heads will properly support your head gaskets. I went with world products steel s/r torquers with 76cc chambers and 2.02 intake and 1.60 valves and a good gasket match and pocket port. had machinist drill steam holes. for sure a mls head gasket, and arp bolts

thanks doggiedave, I had the steam holes drilled in the heads when they were pocket ported and redone. I was running them on the 400 in a 79 Camaro with no problems, the motor ran great with a lot of torque.
Thought I would freshen it up with a marine specific cam and put it in the Liberator to get a little more performance and speed out of it.