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1. Intended use - 18ft light Jet Boat

2. Vehicle info (weight/gearing/trans) - 900lb jet boat hull + 1000lbs engine, fluids, gear, direct drive to jet pump (pto adapter to 1310 spicer u-joint for jet pump shaft). Jet pump is a berkeley 12JE with an AA impeller and inducer freshly rebuilt.

3. Fuel desired to use ( racing gas/av gas/E-85/methonal/pumpgas(include octane available)) - pump 93 octane

4. Parts you already have:

460 that I believe is mostly factory spec (rated at 320hp from the factory (hardin marine 460) but has a re-manufactured stamp on the side so not sure of any of the specs still apply). Never really built an engine from the bottom up but know enough to bolt things together and have enough tools I think I could build one. I rather not have to pay or rely on a machine shop though.
It is currently running but has a tick on 1-4 cylinder bank somewhere. I plan to run a leak test tonight to maybe pinpoint which cylinder. It is down on power. I am guessing stuck lifter?

    Intake: EB Performer 460 Intake Manifold dual pane non EGR #2166
    Carb: Quick-fuel marine carb - secondary vacuum (600CFM, yes I know maybe a tad undersized but maybe not given low compression spec of engine 8.35:1)
    Fuel pump: Mechanical holley 110gph
    Distributor: Pertronix III marine - mechanical advance only. Currently running 10 degree advance at idle 900rpm, 32 all in at 3200rpm.
    Block: 2 bolt main (1970s) externally balanced (see picture)
    Crank: 3YA, externally balanced (see picture)
    Pistons: I believe factory truck cast pistons (see picture)
    Rods: Factory rods I believe (see picture)
    Heads: Not entirely sure. I linked a video believe but I guess D3s but I don't see any casting mark on them. Also I can't tell if the exhaust ports have been ported, some shown the smog bulge slightly and some are flat? (see video/picture)
    Valve Train: Stock I believe but I see a red damper inside the springs I think? (see video/picture)
    Cam: No idea specs or type (if I was to swap the cam I would like to go hydrualic roller cam? given flat tappet issues and lifter quality control, the new stuff won't break in properly from what I have been reading) (see picture but probably can't tell much)
    Timing Set: Stock I think (see picture)
    Oil Pump: Factory front sump with 5 quart pan. I run an oil temp sensor in it given pan size. Don't have the money for a large 10 qt baffled/rear sump one. Also the engine runes relatively cool when under power given open loop cooling with no T-stat. At idle it will get around 170F (water temp) but quickly drop as soon as lake water is circulated through the engine from the jet pump. I haven't really seen oil temp rise above 140F. There is also some lake water splashing around in the bildge area and the pan sits about 1 inches above the bottom of the boat so I guess some of the lake water is also cooling the pan slightly. I run a 10-40W oil per the factory manual but maybe this is too heavy weight given the rebuild done in the past, no idea because I don't know piston/cam specs or anything.
    Exhaust: Marine wet jacketed risers thru transom in an enclosed hatch (aftermarket water jacketed headers aren't really an option $$$$$, maybe logs + snails but might reduce power further but would provide better packaging vs the risers and allow larger valve covers) (see picture)
    Valve Cover: Stamped steel (I hate them, such a pain to seal with steel core gaskets even taping the bolt holes flush), I can't run larger valve covers except the very rare/expensive M/T Ford or Holley ones due to exhaust manifold clearance. (see picture)

5. Proposed Budget - Like $500-1K? Basically just want to spruce it up to around 400hp with a peak rpm of around 4700-5000rpm, reliable lake boat on pump gas. There are machine shops around me but wait time is very long and pricing I would suspect is crazy so rather just be able to bolt things together if i can.

6. Location this may help to find a good machine shop - Raleigh NC Area

Heads video identify?
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