Is the 5.7gm engine still made brand new?

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I'm looking at doing a total repower on my boat and I've always been cautious about remanufactured engines cause some engine builders take short cuts or use marginal parts.

I was thinking of having my vortec 5.7 carbed engine turned into a 383 stroker and just using a reputable shop here in Houston.
 
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https://www.ebay.com/itm/GM-OEM-NEW-CRATE-Engine-350-12530283-Chevrolet-5-7-L31R-DEALER-DIRECT-12681431/301567296304?hash=item4636cfc330:g:uxgAAOSwTC1dUc2L

I purchased one of the L31's from Radley Chevrolet to upgrade a 83 Silverado to fuel injection. Fast shipping, the price was right, and the transaction was handled professionally
 
Originally Posted by rrwildlife
https://www.gmperformancemotor.com/parts/12703983.html

https://www.ebay.com/itm/GM-OEM-NEW-CRATE-Engine-350-12530283-Chevrolet-5-7-L31R-DEALER-DIRECT-12681431/301567296304?hash=item4636cfc330:g:uxgAAOSwTC1dUc2L

I purchased one of the L31's from Radley Chevrolet to upgrade a 83 Silverado to fuel injection. Fast shipping, the price was right, and the transaction was handled professionally


What EFI setup did you use?
 
Holley Sniper


Originally Posted by cpayne5
Originally Posted by rrwildlife
https://www.gmperformancemotor.com/parts/12703983.html

https://www.ebay.com/itm/GM-OEM-NEW-CRATE-Engine-350-12530283-Chevrolet-5-7-L31R-DEALER-DIRECT-12681431/301567296304?hash=item4636cfc330:g:uxgAAOSwTC1dUc2L

I purchased one of the L31's from Radley Chevrolet to upgrade a 83 Silverado to fuel injection. Fast shipping, the price was right, and the transaction was handled professionally


What EFI setup did you use?
 
GM Performance Parts still sells brand new 5.7L crate engines. None are intended for Marine use, Even though the Ramjet 350 is built as a marine engine (Has marine head gaskets/Brass core plugs) though I would upgrade the valve springs!!
*Some marine engines are reverse rotation, Something you need to know before doing anything.

I'm by no means a marine engine guy......Know just enough to be dangerous!!
 
You would look at the balancer pulley on the front of the engine. If it turns clockwise it is the same as a car engine.
 
Originally Posted by Chris142
Originally Posted by AVB
Aren't boat engines reverse rotation?

Some are. If it has 2 engines one will rotate backwards to that the boat won't go lopsided.


Just mount one of your props backwards.
smile.gif
 
The 5.7 small block engines in boats were 4 bolt mains, similar to a truck 5.7.

There is a difference between rebuilding and remanufacturing an engine. The big companies that do engine remanufacturing have machines that the local rebuilders cannot afford. And a reman engine always changes a set number of parts whether it needs it or not. A rebuilding will change worn parts.
 
Originally Posted by motor_oil_madman
I'm looking at doing a total repower on my boat and I've always been cautious about remanufactured engines cause some engine builders take short cuts or use marginal parts.

I was thinking of having my vortec 5.7 carbed engine turned into a 383 stroker and just using a reputable shop here in Houston.


The rest of the power train needs to be able to handle the increase in power.
 
It has a 4 bolt mains already and vortec heads. What else does it need? to be a 383 it will need a new crankshaft. connecting rods, etc.
 
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Originally Posted by motor_oil_madman
It has a 4 bolt mains already and vortec heads. What else does it need? to be a 383 it will need a new crankshaft. connecting rods, etc.


You can run the factory 5.7" rods, The pistons will need to be swapped (Higher wrist pin height). You can also run 5.565" 400 rods but new pistons are still required.

383 is technically a .030" overbored 350/327 (4.00") block with a 400 3.75" stroke crank, We used to turn down 400 cranks before companies like Scat started offering cast & forged cranks just for this.

The increased stroke may not the best thing for a marine engine that spends its entire working life at higher RPM's, Sure.....If it's balanced well & you use top shelf Forgings, It may last longer than the original 350. Use bottom of barrel cast crank, Recon forged or powdered rods, & Cast pistons....Don't expect much in the way of longevity.
 
Look at Blueprint Engines. Plenty of engine builders out there, but I see them on different YouTube channels and car magazines. They have various GM marine engines they built starting at $4500.
 
You did not say if this is for freshwater or saltwater. Do not use a regular engine in a boat that will be mostly used in saltwater.
 
Originally Posted by Blueskies123
You did not say if this is for freshwater or saltwater. Do not use a regular engine in a boat that will be mostly used in saltwater.


It's saltwater
 
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