Engine block size

[KD4UPL]

So with 17 inches of snow yesterday I'm feeling better by looking for a new boat. I'd love to have an 8.1 big block but they quit using those in boats. I know, GM quit using them too, I get that. Which got me to thinking; GM hasn't used the 5.0 or the 5.7 in many years yet they are still in boats. Where are they getting the blocks for these engines? Why haven't boats started getting 5.3L and 6.0L engines in keeping with the GM lines? Why can't we still have an 8.1L (or a 7.4 for that matter) if we still have 5.0 and 5.7?
I'm sure someone on here knows. I'm just curious.

 

[achris]

I think you'll find the blocks you mentioned are aluminium. Merc got its fingers well and truly burned with the '470' and aluminuim in marine inboard engines. The need for a dedicated heat exchanger, and the associated problems may have spooked them good and solid.... That said, the Merc latest V6 Mercruiser is and all in-house designed and built seems to be some sort of hybrid of cast iron and aluminuim... :noidea:

And that might be the other reason Merc hasn't gone to the trouble of developing the new GM engines, because they knew they were introducing their own line...

Just my thoughts....

Chris...........

 

[Bondo]

Ayuh,.... Crusader, 'n a few others are buildin' Marine rated 6.0l Chevys,.....

Donno where Merc is headed,...
I Am sure that we're headed for some big changes rather soon,....
I figure, I can use SBCs, 'n BBCs til I die, there's enough used iron out there ready for rebuildin',....

 

[lg260ss]

Volvo Penta has been using the GM l96 6.0l for a few years now. They have 3 versions available , 350hp, 380hp, and 430 hp. I own a 380 and it is an awesome package. Fully closed cooled, VVT, and significantly lighter than a BB give it huge advantages.
Volvo has also announced that they will be using the next gen 4.3 l. Two versions of that engine will be available 240hp and 200 hp.

Merc on the other hand went back to their 8.2l after GM stopped making the 8.1l. GM had to stop making the 8.1 because of the new EPA regulations.