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Low budget 7.4 rebuild

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Old 07-24-2016, 05:21 AM
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Default Low budget 7.4 rebuild

I just bought a project boat with a '96 7.4 Mercruiser and Bravo 2. Factory exhaust had never been changed and the engine ingested water before sitting for 2 years. My plan is to replace the short block and have the heads rebuilt. Thinking of picking up a truck gen v shortblock from a wrecking yard (approx $150) and having it rebuilt - I like the idea of a block that's had green stuff in it. Freshen up the existing heads and throw on a FWC kit, new exhaust, new intake, carb and cam.

What might I want to do to squeeze a little more horsepower out of the engine while I'm in there? Not looking for a race setup... It's in a 27' sport cruiser... Is a gen vi block ok if I don't have any gen v available? Terrible idea to go with Chinese Pro Comp aluminum heads while upgrading to roller tip rockers? Objective is reliability, efficiency and a little more power.

Greatly appreciate the assistance!
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Old 07-24-2016, 05:50 AM
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The words low budget and boat do not work together.
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Old 07-24-2016, 06:03 AM
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different people have different ideas of what defines "low budget"...What is your budget ?
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Old 07-24-2016, 06:58 AM
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I'd like to stay under 4k without including the FWC kit and exhaust. So that includes short block heads intake cam and carburetor.
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Old 07-24-2016, 07:31 AM
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I can probably save a little $ rebuilding the original carb. And of course I know if I go with an automotive block, I'll need marine freeze plugs and head gaskets...
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Old 07-24-2016, 09:14 AM
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Also I would want to be able to run 87 octane
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Old 07-24-2016, 09:54 AM
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Why can't you use the parts you have? I just rebuilt a 96 small block that had water sitting in it for 2-3 years. I had to drive the pistons out with a steel pipe. The block was checked for cracks and bored .40 over. Used the same crank, cam. I had $1500 in machine shop alone.
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Old 07-24-2016, 10:01 AM
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This has all been covered many many MANY times before. Tim (Fullforce) on here has some 420's I think, fairly fresh that would save you a LOT of money and grief. While your taking to him, ask him about procomp heads.
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Old 07-24-2016, 12:05 PM
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Look up repowering of a brick. Excellent thread. You will see all the gains in speed that are available
.
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Old 07-24-2016, 05:32 PM
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Thanks the recommendation. Reading more, I'm thinking to stay with factory spec lower end and heads (rebuilt) with a stainless thru hull which will allow a more aggressive cam. Add a dual plane intake and a fresh carb and I should have a reasonably reliable upgraded motor. Thoughts?
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