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Last week I purchased an 1976 Omega 21' Open Bow with a 460. The previous owner had said that he went through the engine and freshened it up recently. When we started it upon purchasing it it was reading 55 psi cold. Well I bought it and took it to the lake and about 15 minutes into it I have 0 psi at idle and 25 psi full revved. The tach is showing me 5500 rpms ( either the tach is off or im crazy but the engine sounded like it may have been spinning 4000 rpm's and was going maybe 40) Either way upon pulling the engine that night I found that ALL bearings are dust, and the cylinders are scored. I have since purchased another block with fresh heads (D3VE) that already has the upgraded springs and stainless valves but no port work. It also has .030 over trw 2404 18cc dish pistons in it. I am replacing all the bearings in it just to be safe and am looking at the Comp Cams XM270H cam for this build. Between the two engines I have a edelbrock perfomer intake and an offy dual port 360. Strongly considering the weiand stealth but think the performer will suit the build well. Also I have two holleys the model 7010 (a 4160) 780cfm vacuum secondary and a 750 dp. I have two sets of fresh d3ve heads as well. The boat has through transom hardin logs and I have no clue what impeller is in the jacuzzi wj pump. Maybe you gurus can help me figure this out. I am going to rebuild that along with the engine to ensure the tach wasnt right which would explain the rpm's relative to the speed. I have a chance to get a new set of trw 2443 dome pistons that will bump my compression to like 10.5:1 as well for 400 new or 300 for a used set. Also I have a stock truck oil pan on it so am wandering about the need for a hv oil pump or not and if any oiling mods need to be done. I am willing to spend the money for whatever is needed. I would like a good healthy hp boost as I expect my boat to run like my kx500 if you know what i mean. Reliability is first on the agenda though. I would like to make 450 -500 HP and have this all done by next week so I would really appreciate some input and feel free to spend to build it as if it was your money ($1800 budget) Thank you all ahead of time.
 

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1) buy a bigger pan if possible, check for clearance, if not I like to use oil restrictors, if you run it hard with a small pan, you will notice the oil pressure low after a hard run, it will be fine just cruising, but keep an eye on it. My experience with Ford is that they pump all the oil to the top of the motor.
 

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I agree with LED on his comments. Sounds like the first motor was ran out of oil. It probably had the stock 5qt, front sump pan with stock front oil pick-up, correct? If you are building 450 to 500HP you need a 10qt pan with a remote rear pick-up.

I like the Stealth or the Victor in a Jet boat along with a 750DP stock, 850DP for 500HP. The TRW pop-ups work pretty good. You will need to do some port work on the heads so they can breath. Were the heads upgraded to roller rockers?

Let see some picks of the boat.
 

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Next week ain't that far off. I have friends with Ford engines in their boats. They recommend you put on a 10 qt DOOLEY Pan, Tray & P/U along with a Melling SCJ Oil Pump. You should have about $1000.00 left over to buy a NOS Big Shot system for the 780 Carb, and enough to install it & fill up your bottle. Set that on 275 and you should be fine.

I would probably do something else if I had more than a week, but that's all(?) you have.
 

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Same cam I used, you will need the heads worked to make that hp. Sell the performer get a stealth. Heads need at least 315 cfm on intake. Exhaust will need 180cfm. With little work I got 315 intake 304 exhaust. I put bigger exhaust valves in tho. With that combo I got 500 hp easy.
 

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1) buy a bigger pan if possible, check for clearance, if not I like to use oil restrictors, if you run it hard with a small pan, you will notice the oil pressure low after a hard run, it will be fine just cruising, but keep an eye on it. My experience with Ford is that they pump all the oil to the top of the motor.
Alot of the stock & perf BBFs have have a huge problem, the oil drain back. To fix it you will first need to check the head and block oil drains the next will be the lifter valley. I always increase the size of the drains and tapper them like a funnel in the head and valley. A good High Flow Dynamics Oil pump that the block has been fitted for helps as well.
 
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