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Big Block Chevy Re-build

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Old 03-15-2009, 03:26 PM
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Default Big Block Chevy Re-build

I am wanting to rebuld my 454's in my 90 scarab super sport. I have some questions. I would like at least 500hp. Doesn't have to be a race boat, just a little faster. Can I get this with no reliability issues? Should I build it to supercharge instead? Which will be the most economical and but also the most reliable?

I was thinking:
decent cam
bore a little over
9.5 or so compression
aftermarket heads
good intake
good carb


Ideas?
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Old 03-15-2009, 05:51 PM
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Originally Posted by Jeff P31
You won't need a supercharger to make 500 hp . With the parts you have listed you will make over 500 easy.
i agree,if u go with aluminum heads,and the right cam,you can go a little higher with the compression.
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Old 03-15-2009, 06:25 PM
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Stroke the engines to 489 or 496, aftermarket exhaust, roller cam, rework heads, intake, ect.. I have been talking to RMbuilder (Bob) about a cam. He can grind a cam to whatever you are looking for. Good luck!!
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Old 03-15-2009, 06:41 PM
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Originally Posted by jeffswav
Stroke the engines to 489 or 496, aftermarket exhaust, roller cam, rework heads, intake, ect.. I have been talking to RMbuilder (Bob) about a cam. He can grind a cam to whatever you are looking for. Good luck!!
Yes Bob is the man to call !!!!!!

Bob Madara of Marine Kinetics 585-654-8583
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Old 03-18-2009, 06:28 PM
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It is a saltwater boat. So am I right in saying as long as I flush the cooling system with clean fresh water after every jaunt in the ocean I am ok? Or will it still be a corrosive nightmare?

Thanks for the help too.
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Old 03-18-2009, 07:19 PM
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If they are 19 year old salt water engines, it is quite possible that they are pretty much destroyed inside already. You would probably be better off to buy some good take out engines if thats the case.
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Old 03-18-2009, 07:37 PM
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Originally Posted by Griff
If they are 19 year old salt water engines, it is quite possible that they are pretty much destroyed inside already. You would probably be better off to buy some good take out engines if thats the case.
What he said.

You just need to see how the blocks look as far as how destroyed they are.

454 is a good engine due to all the options available for it.

Bore it .060 and raise the comp to high 9's. Get some nice heads and a cam from Bob Madero.

He'll get you a good recipie.

You didn't say what kind of exhaust you have though and that is your biggest issue. If it is still stock, forget about it. Best case, you need a tube header of some sort.

Good luck.
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Old 03-18-2009, 07:52 PM
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Guess I should have clarified.

Remans, extremely low hours. One manifold cracked leaked into combustion chamber. Seized one engine. I do not have to redo both just am pondering doing so. Everything is completely stock. Keep in mind it is a center console. I am sure the 330's are plenty but 500's would be better.
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Old 03-18-2009, 07:57 PM
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Originally Posted by thermasystems
Guess I should have clarified.

Remans, extremely low hours. One manifold cracked leaked into combustion chamber. Seized one engine. I do not have to redo both just am pondering doing so. Everything is completely stock. Keep in mind it is a center console. I am sure the 330's are plenty but 500's would be better.
With stock exhaust you have almost zero potential for upgrading the cam and or the bottom end. The biggest hinderance on those engines is the peanut heads and the exhaust.

Without an exhaust upgrade, I would order a set of Merlin oval port heads set up and ready to go for that flat tappet cam and upgrade the intake and carb. You will notice a difference, and when you decide to spend the coin for the exhaust, then you upgrade the bottom end.

The money that you all ready spent on the top end, will bolt right onto the new bottom end. By that time you can polish up the runers on those ovals and get a good cam cut and up the comp etc, and you will be where yo uwant to be.

Can't do anything realistic without the exhaust though.

Good luck
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Old 03-18-2009, 08:20 PM
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Stock 330's should stay stock. For any decent upgrades with a noticeable hp increase, you'd end up replacing most of whats in them. Better off to sell them and start with engines more suited to hp upgrades.
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