GM Marine Engines are on their website now

[kfennell]

So you can see the difference between the "OEM" specs of the old vs new GM marine engines, it looks like a 35 HP bump on the big engine and 60 hp on the smaller ones.

 

Another interesting change is that they will have variable displacement, I bet that will save some money for those of us who have 50+% hours at idle.

 

http://www.gmpowertrain.com/MarineEnginesControllers/ProductPortfolio.aspx

 

I know there are manufacturers who have already received these engines for testing and that "they will cost substantially more" then the 2015 engines. Does anyone have anything more concrete then this? Will 5.3's with 350++ horsepower be available?

[oldjeep]

Be curious to see how variable displacement plays with marine use. The oils that they have to use with them are really light. Also not sure that the increased cost of the engine and all the extra stuff on the motor to maintain is going to pay for itself in fuel.

 

That being said, the version of variable displacement on my Ram has been trouble free for 115K miles so far although it is pretty rare that it actually kicks and the Ram system doesn't operate at idle. Anyone know if the chevy version operates at idle?

[oldjeep]

@kfennell After looking at the specs some more, where do you see variable displacement? I see variable valve timing but not anything about cylinder deactivation.

[kfennell]

It is in the printable PDF: http://gmpowertrain.com/2013_pdf/M_Vert_Gen5_6.2(L86)_020315.pdf

[oldjeep]

Ah, ok part of what they are calling Active Fuel Management. Googling that shows that at least the truck version of that system does operate at idle.