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Was wondering if someone with real know-how could explain to me why a chevy big block crate motor will not work in a marine application. The 572 720hp motor looks killer but engine builders in my area say it wont work and will blow up. Same with evey other crate motor, 502, 454, ect. Any info would help.

Thansks
 

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They are nice pieces for a reasonable price.
May be a tad tight clearance wise for marine use as shipped but many are using them with good success.

Is that your's Outlaw??
If so you should be a good source of info!
 

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Everyone I know that's used one of the GM crate motors has been happy with it. I haven't done one in years, but the last couple I did, I took apart and checked everything out. Most issues were minor...
With a lot of engine builders, whatever you have is junk and should be throw away. Whatever anyone else built is NFG and you will be lucky if it even runs. Anything your last engine builder told is wrong (this is can be true even if it's the same guy and some time has passed).
All engines are compromises in some way... Ask lot's of questions, use a bit of common sense and make your mind up what's best for you...Good luck :)devil
 

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21 Daytona
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They are nice pieces for a reasonable price.
May be a tad tight clearance wise for marine use as shipped but many are using them with good success.

Is that your's Outlaw??
If so you should be a good source of info!
no not mine Its off hi tech's web site
 

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steelcomp was here
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Everyone I know that's used one of the GM crate motors has been happy with it. I haven't done one in years, but the last couple I did, I took apart and checked everything out. Most issues were minor...
With a lot of engine builders, whatever you have is junk and should be throw away. Whatever anyone else built is NFG and you will be lucky if it even runs. Anything your last engine builder told is wrong (this is can be true even if it's the same guy and some time has passed).
All engines are compromises in some way... Ask lot's of questions, use a bit of common sense and make your mind up what's best for you...Good luck :)devil
I frequent a few other website forums where there's a little higher level of racing participation, and I've heard plenty of horror stories about these and other crate engines. Mostly due to poor clearances/oil pressure issues, and power that's no where near advertized. My advice is, when ever you buy a crate engine, at least tear it apart and inspect it closely. All it will cost you is gaskets, and some time, but it may save you lots more in the long run. My guess on the marine issues is they're not built for marine use, so they're going to have all kinds of disclaimers.
Just my .02 FWIW
 

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GM crate engines are not warrantied for marine use unless the specific model crate engine is designated for marine use by GM. So, you could drop 12K in a 572 and your on your own as far as warranty goes.

Jay
 

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Plenty of out of the box motors have gone in ski boats over the years. It would be a matter of application, IMHO. If you're going to run around, ski, a few blasts, probably fine. If you think you're gonna wring it out and beat the crap out of it, have your builder tear it apart and clean it up for a couple grand.

No free lunches...
 

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The 502 dyno sheet that I posted on the other thread started life as a GM short block. I had ESI pull it a part and blue print it. As Warp stated the clearances are a bit tight for marine use. I know people have just droped them in a boat, but my friend wanted an engine that would last for year's with out any issue's. The blue-printing was money well spent.

As Scott said ,I would have one torn down and checked out. I do have a friend that blew up their crate engine (502) 3 times last year. Chevy replaced it the first time, it blew again then Chevy tried to fix it for them twice blew each time. I told them after the first time to take it to an engine shop and blue print the damn thing. Some people have more money than brain's.

Sleeper CP :D
 

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E-7 Sheepdog (ret)
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Was wondering if someone with real know-how could explain to me why a chevy big block crate motor will not work in a marine application. The 572 720hp motor looks killer but engine builders in my area say it wont work and will blow up. Same with evey other crate motor, 502, 454, ect. Any info would help.

Thansks
The cause for concern is with the clearances because you are using cold lake water to cool the motor. I don't know the exact specs of this crate motor but a few other things to look at are the cam specs, brass freeze plugs and fittings, and a larger oil pan.
 

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21 Daytona
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Duane says that is one great jet boat motor, out of the box.

Just has lousy results out of the Demon carbs on them. I think he has a whole closet full of them available CHEEP. :D

just what part # do they put on the 572? How cheap??? I need one for my
68 El Camino
 

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E-7 Sheepdog (ret)
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Was wondering if someone with real know-how could explain to me why a chevy big block crate motor will not work in a marine application. The 572 720hp motor looks killer but engine builders in my area say it wont work and will blow up. Same with evey other crate motor, 502, 454, ect. Any info would help.

Thansks
Lies:)

I have two crate motors. a 2000 Gen VI 454 HO in my 21' Eliminator Daycruiser with about 100hrs on it. Runs flawlessly

2008 Gen VI 502/502 short block for my motor in my race boat. With the top end combo and AFR heads and a dart tunnel ram. Pushes my 19 Daytona to 113mph at 9.25 at Lake Ming Last weekend.

These two motors are the best ones I've ever had.
 

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Boat Nut
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Lies:)

I have two crate motors. a 2000 Gen VI 454 HO in my 21' Eliminator Daycruiser with about 100hrs on it. Runs flawlessly

2008 Gen VI 502/502 short block for my motor in my race boat. With the top end combo and AFR heads and a dart tunnel ram. Pushes my 19 Daytona to 113mph at 9.25 at Lake Ming Last weekend.

These two motors are the best ones I've ever had.

I've ran the ZZ502 aluminum heads in marine use for 8 seasons. no problems, they were gone thru when new, guides reamed, and inconel exhaust valves. Motor is apart for freshen up, heads still look great, no corrosion in the water passages.
 

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E-7 Sheepdog (ret)
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And you will not likely get any corrosion in the water passages unless you start parking it for weeks at a time in a slip in the water continuously.

Put it on the trailer, the water drains out of the heads and upper block, the engine heat dries them, moisture required for galvanic (dissimilar metals) corrosion is gone.
 

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We've used over 20 of the 572 motors. Of all of them used, we've only had trouble with one. He has blown it up three times. But no matter who builds what for him, he will blow it up. The clearances are pretty tight for a marine application, but with a long easy break in, they seem to survive just fine. We've ran about half of them on the dyno. Only two of the ones we ran dynoed under their rated HP. One major problem that we've ran in to with them is the Demon carburetors and the intake manifolds that come on them. We use an innoivators system to check the fuel mixtures. When hooked up to the collectors side to side of engine, the mixture reads just fine. But when we hook up the innovators 8 channel system, one to each cylinder, we find 4 very rich cylinders and 4 cylinders lean enough to detonate. All you have to do is put a Super Sucker under that Demon and it will straighten it right up. Then send the manifold to Rehor-Morrison, they will rework the dividers and you pick up another 11 to 19 hp and the mixtures get near perfect. I just pulled some records and one of the motors we dynoed went like this. 720Hp - 572 crate motor out of the box dynoed 724HP. Put a super sucker under the carb and got 738HP with a lot better A/F ratio. Put a Holley out of the box on it and only got 2 more HP, but the mixtures were better yet. Sent the manifold in and run it again and it went to 758Hp. We put this motor in a jet boat and he won the championship in his class that year. The next year he put a N2O set up on it that would go to 500 hp and he is still running it. I don't think he ever sprayed over 350hp though. Oh, BTW we put a Basset 10 quart oil pan on every one of them. This has been my experience with them. Now, on the 502 crate engine, I've never got one that would dyno at or above 502 HP.
 

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E-7 Sheepdog (ret)
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We've used over 20 of the 572 motors. Of all of them used, we've only had trouble with one. He has blown it up three times. But no matter who builds what for him, he will blow it up.
Hmmmmmmmm..............


Pretty funny actually, since that isn't me. :D :)hand
 

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GMPP motors

There have been some problems with the oil pump drive shafts. You might as will update the oil pump while you are there. Cheap insurance. Al
 
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