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Old 10-06-2010, 09:02 AM
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Default Repower project questions

I blew up one of my new engines with around 350 hours on it, and found out it was a rebuild when we tore it apart to inspect it. Obviously I'm a little gunshy and not-so-trusting now that I found out this guy in Rockville, Maryland sold me rebuilds as new.

I have to assume the other is a rebuild as well, so I'm selling it because I want two brand new engines, start fresh. Planning to keep the intake, carb, valve covers, exhaust and bolt on accessories for the new engines.

1. Not sure what I can get for the good engine, so that would be one question I have. It runs like a watch, doesn't have a lot of scaling because we boat in brackish water. The only reason I blew up the other is because a $150 Holley Marine Fuel pump crapped out on me and leaned it out while running 3500rpm. It finally broke loose a few weeks later.

2. I'm in the market for two engines now, 450 to 500 horsepower, able to run on 89 octane, reliable and dependable. I don't run WOT, usually 3500 RPM all day. 502's seem to be hard to find in stock, and prices are all over the map from $5k to $7k. Merlin 509's might be a good option, looking for some first hand experience and thoughts from you guys.

3. Why are 502's so hard to find right now, is GM retooling or something?

Thanks in advance.
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Old 10-06-2010, 09:22 AM
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If you use the right parts a rebuild is better that any crate motor. I prefer to pick and choose the internal components. Use a forged crank, rods, pistons, roller cam (from RMbuilder) and you are good to go. What do you have now?
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Old 10-06-2010, 09:41 AM
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Originally Posted by jeffswav
What do you have now?
All I have are the 2 existing engines, the one is perfect, runs great with no problems. The other is just completely shot, but I think I can still use the heads from both. We can't find the CAM numbers anywhere, so not sure what brand or grind they used. It had KB pistons in it. Not sure about the other parts and what I might be able to reuse just yet. Planning to pull and scope the good engine soon.
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Old 10-06-2010, 06:55 PM
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I assume they are 454's? You can get the casting numbers off the engine they are on the front left looking at the engine. The casting numbers for the heads are under the valve covers.
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Old 10-06-2010, 08:29 PM
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They're 502ci, 450HP's. The cast iron heads are probably reusable but I've decided to start with new, and since I'm going with a closed cooling system, the possibility of using aluminum heads enters the equation.
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Old 10-06-2010, 09:52 PM
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Exactly what does "new" mean to you?????

Even brand new stuff needs machining. Use what you've got and have it rebuilt by a reputable builder.
It will as good or better than "new"

If you want brand new everything, then you better get ready for a 30k price tag.
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Old 10-07-2010, 01:28 AM
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Originally Posted by Keith
All I have are the 2 existing engines, the one is perfect, runs great with no problems. The other is just completely shot, but I think I can still use the heads from both. We can't find the CAM numbers anywhere, so not sure what brand or grind they used. It had KB pistons in it. Not sure about the other parts and what I might be able to reuse just yet. Planning to pull and scope the good engine soon.
Find someone with a "cam doctor" to check it for you, if you need we offer the service. I can produce a card for the stick you have.
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Old 10-07-2010, 09:58 AM
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Keith, please let me know who sold you the "new" motors so I don't use him in the future

Thanks
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Old 10-07-2010, 10:28 AM
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New does not always mean better !!!!
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