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Old 09-13-2011, 11:12 PM
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Default Repowering a 28ZX with twins

I have a 2005 28' ZX. I am going to repower the boat this winter. It was involved in an accident, which ripped the Bravo 1 drives off. While the authorities did their investigation, they wouldn't let me get the water out of the engines. That was 3 weeks ago, so I am figuring the engines are going to need major internal work. The repairs are on the other boat's insurance claim, as he was at fault. Currently the boat has twin 6.2's I am debating on spending the extra money and looking at either the 383 Scorpions or the 496HO. But I have always been told you can't replace cubic inches. Should I consider the 496 HO's or does the additonal weight make that counterproductive over the Scorpions. The 500 EFI is an option as well. The 502 isn't as much of an option due to the fact that those aren't current motors any more. What does everyone think?
Thanks,
Adam
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Old 09-14-2011, 02:21 AM
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didn't they bring the 502 back? Maybe see if ilmor can put there new mv8 7.4 in there! Won't insurance only restore it back to what it was originally though?
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Old 09-14-2011, 07:59 AM
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I'm not sure where you are located, but Jeff Cropper in LI, NY just rebuilt a pr of small blocks for a 28powerplay owner, and he is very happy. Mid 400hp if i remember correctly.

Link to this powerplay...
http://www.offshoreonly.com/forums/p...-restored.html
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Old 09-15-2011, 06:57 AM
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I just spent the last couple of evenings with a buddy of mine in the Donzi Club that repowered his 28ZX with twin 400 small blocks (originally had 350's) putting out around 500hp each. running in the low 90's, still playing with props.

Not sure how the big blocks would affect the balance of the boat, keep us posted,

tom
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Old 09-15-2011, 06:54 PM
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I am concerned about the balance and size of a big block as well. The boat already sits low in the rear with the 6.2's. I think the 502 would fit, but I don't know how much room would be left for the exhaust headers, let alone changing a spark plug. That's why I like the idea of the 383 scorpion. Thanks for the ideas.
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Old 09-15-2011, 06:56 PM
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Some 28zx's came with 383 scorpions and they ran near 80. That is a great package IMO.
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Old 09-15-2011, 09:14 PM
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Actually the 496 is discontinued by GM but 502's are still produced by the performance parts side of GM. Mercury is calling them the 8.2 Mag.
The Scorpions are the ticket unless you have something built.
Originally Posted by abooth55
The 502 isn't as much of an option due to the fact that those aren't current motors any more.
Thanks,
Adam
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Old 09-15-2011, 09:43 PM
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Originally Posted by abooth55
I am concerned about the balance and size of a big block as well. The boat already sits low in the rear with the 6.2's. I think the 502 would fit, but I don't know how much room would be left for the exhaust headers, let alone changing a spark plug. That's why I like the idea of the 383 scorpion. Thanks for the ideas.
I would just put two nice small blocks back in,there are many choices.If you get rid of the cast iron exhaust and go with either aluminum manifolds or headers the boat will sit higher as its around 250lbs lighter in the rear.At least my Formula did.


Plus if you go big blocks you will have to upgrade the drives,small blocks and bravos cheap to run cheap to fix..........well cheaper than 700s and 6s.

Last edited by Expensive Date; 09-15-2011 at 10:47 PM.
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Old 09-17-2011, 09:01 AM
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get u a pair of scorpion smallblocks,bolt on some whipple chargers and some lightning headers,and you will have a 90-95 mph very fun to drive boat!!!
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Old 09-19-2011, 06:28 AM
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What about the new LS style of motors?
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