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-   -   Difference Between Boat and Car Engines (https://www.offshoreonly.com/forums/general-boating-discussion/171063-difference-between-boat-car-engines.html)

excalibur32 10-17-2007 01:19 PM

The alt and starter dist, etc. have spark protection and should be coast guard approved.

David Stotz 10-17-2007 05:28 PM

When GM was making the old style small block 350 and 305 for passenger cars and trucks, how many do you think they made a year. As a percentage, how many went into boats? I think this is where you will find the answer to the great debate.

Michael1 10-17-2007 10:38 PM


Originally Posted by fandango (Post 2307511)
Can anyone (specifically anyone who works/worked for either company or has FIRST hand knowledge- not I know someone who knows someone) answer the question of what is the difference between the short block that GM performance sells -ZZ502 - and the shortblock that come with the "marine engines" from 1800runsnew and the likes. We are talking about only the shortblocks (not heads, cams, etc). You can buy a GM ZZ502 shortblock for approx $ 4400 I think and the 1800runsnew total engine is about $ 5400. Is someone taking apart these shortblocks, changing/checking clearances, balancing and reassembly, and then charge only an extra $1000 for the entire motor?? Point is I have heard that the 415 horse 502 comes from a plain GM performance shortblock (forged piston, steel crank, 7/16 rods etc.) and the 500 hp was disassembled and changed/checked, balanced and reassembed. Sorry for the long post.

I spoke to a high volume marine engine manufacturer recently, and one of their engines is based off the ZZ502. They just get a GM crate engine, replace the valves with Inconel, put it back together, and dress it. That's it. He's says they have had no problems.

This is not to take away from what people have mentioned here. The higher the performance, and load, the more changes you should be making, including changing clearances, etc.

Michael

Liquid Liability 10-18-2007 08:15 AM


Originally Posted by Bigyellowcat (Post 2306089)
paint it blue and put a mercury sticker on it and you will have magically turned it into a marine engine.

:D:D:D

ZBODaytona 10-18-2007 08:29 AM

Didn't eliminator take the 572 motor from gm, change the cam and put it in a boat. Thought i read in magazine that they did and it worked good. Of course i don't think they said how long it worked good.


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