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-   -   GM 6.0L small block marine engine (https://www.offshoreonly.com/forums/general-q/170327-gm-6-0l-small-block-marine-engine.html)

Pat McPherson 10-04-2007 09:18 AM

GM 6.0L small block marine engine
 
Why is Merc not using this engine?
Big block power, small block size and weight...
http://www.gm.com/explore/technology...LY6_Marine.pdf

1BIGJIM 10-04-2007 09:38 AM

Interesting article.

The big questions is how much $$$$

Pat McPherson 10-04-2007 09:50 AM


Originally Posted by 1BIGJIM (Post 2294815)
Interesting article.

The big questions is how much $$$$

Well the Crusader 370HP 6.0L is like $10,600...

http://www.1800runsnew.com/NLM/crusa...gines-NLM.html

handfulz28 10-04-2007 11:06 AM

Pat, I've been asking this question for over a year...since I found OSO. My only guess is a resistance/inability to invest in new tooling for things like exhaust (different flange/port) and closed-cooling (warranty issues...salt+aluminum).
Crusader, Indmar, Marine Power...they all offer a version of this motor.
Here's a brainfart...perhaps Merc will surprise the boating community and offer this engine, with full O2 sensor and catalytic converter technology to comply with the eco-nazis...
I'd love to see a package with displacement on demand for idle zones and the new variable valve/cam timing system.

Chris Sunkin 10-04-2007 11:18 AM

Off the top of my head...

1. Bigger equals stronger. I have commercial trucks. My Cats put out equivalent horsepower to my Ford 6.0's and Duramaxes. They weigh more that twice but they last 3 or 4 times as long. No substitute for brute force.

2. The current platform is doing quite well- why change? The weight gain relative to the overall boat weight is fairly insignificant. It could easily be equalled by the big-block with alloy blocks, without changing any tooling.

3. More parts = more to go wrong. Technology is wonderful until it doesn't work. All that variable valve timing stuff does wonderful things but it's far from foolproof.

4. That's one fugly motor.

Pat McPherson 10-04-2007 11:43 AM


Originally Posted by Chris Sunkin (Post 2294958)
That's one fugly motor.

Well this version is not so fugly...:D
http://www.pcmengines.com/NewFiles/Z...ec%20Sheet.PDF

I'm not so much suggesting to replace the big block but to replace that 320HP/6.2L. The Merc 6.2L does not produce that much more than the 350MagMPI but does cost a lot more.

I think this would be a great engine for 27' to 32' twin engine performance boats.
Maybe Merc Racing should add it to their line?

Chris Sunkin 10-04-2007 11:54 AM

Yeah, it's not like the 496 is a beauty queen.

http://www.mercurymarine.com/engines...ves/mpi496.php

The manifold cover helps

handfulz28 10-04-2007 12:34 PM

Re-analyze based on it being a small-block replacement, not a big block. And that's part of the problem from a perception point of view. The peak numbers make it comparable to a big block, but the area under the curve doesn't support that comparison. But the numbers also put a traditional small block to shame. It ends up not fitting in Merc's lineup.

The VVT is my wish; the marine 6.0 doesn't have any of that stuff.

I'm curious how large a percentage of GM's "old" small block business comes from Merc and Volvo. Is there that large a demand on the industrial side, outside of marine, that will continue to support those castings? How much longer before GM sells that business line? Perhaps Brunswick will enter the foundry business. They might get that cheaper than the development R&D for new engines.

excalibur32 10-05-2007 07:44 AM

Brunswick is in the foundry business, they are one of the largest "lost foam" casters around.

excalibur32 10-05-2007 07:46 AM

Mercury built the Corvette ZR-1 for Chevrolet, that would be a nice boat engine at 427 cu in.

Pat McPherson 10-05-2007 08:44 AM


Originally Posted by handfulz28 (Post 2295092)
The VVT is my wish; the marine 6.0 doesn't have any of that stuff.

If VVT = variable valve timing, the GM 6.0L marine does have it.
http://www.gm.com/explore/technology...LY6_Marine.pdf

How about the Raylar stroker?
http://www.raylarengine.com/550_engine.html
It looks like a modified Vette engine.

handfulz28 10-05-2007 09:32 AM


Originally Posted by Pat McPherson (Post 2296166)
If VVT = variable valve timing, the GM 6.0L marine does have it.

How about the Raylar stroker?
http://www.raylarengine.com/550_engine.html
It looks like a modified Vette engine.

No kidding! I hadn't read the '08 specs. Oooof...I wonder how long before, or IF, the aftermarket will tackle making a cam for that system. And it sure won't be cheap. I have to say the curves on that motor just don't look marine friendly.

Raylar's piece will be unique. It's great that they're tackling it, but at an estimated price of $20k, it doesn't appeal to the mass market.

VetteLT193 10-05-2007 10:43 AM


Originally Posted by Pat McPherson (Post 2295008)
Well this version is not so fugly...:D
http://www.pcmengines.com/NewFiles/Z...ec%20Sheet.PDF

I'm not so much suggesting to replace the big block but to replace that 320HP/6.2L. The Merc 6.2L does not produce that much more than the 350MagMPI but does cost a lot more.

I think this would be a great engine for 27' to 32' twin engine performance boats.
Maybe Merc Racing should add it to their line?

Last I checked the 350 Mag MPI was in the low $6,000 area ($6,200) rings a bell. The 6.2 is about a grand more than that and even though on the surface only looks like 20HP, it's a much beefier and more powerful engine.

The real deal is the 6.2 repower package. comes with basically everything you need to repower, including the drive and related components. Bravo 1 package is about $12k, Bravo 3 package is about $12.5k

Pat McPherson 10-05-2007 11:00 AM


Originally Posted by VetteLT193 (Post 2296337)
Last I checked the 350 Mag MPI was in the low $6,000 area ($6,200) rings a bell. The 6.2 is about a grand more than that and even though on the surface only looks like 20HP, it's a much beefier and more powerful engine.

The real deal is the 6.2 repower package. comes with basically everything you need to repower, including the drive and related components. Bravo 1 package is about $12k, Bravo 3 package is about $12.5k

The pricing you are referring to is for remanufactured engines and drives.
A new 320HP 6.2L Bravo I is like $20,000... the 350MagMPI Bravo I is 17K.
http://www.mercruiserparts.com/mercr...ive_engine.asp

SkiDoc 10-06-2007 05:24 AM

My Ski Nautique has the 6.0 L P.C.M. Motor in it. They rate it at 375 hp. Great motor but seems to not really have much more low end torque than the 5.7. Runs smooth as a Swiss watch though. I believe there was an A.M.T. cat that had these motors and ran very well!


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