I don't know why they didn't just use the new generation of GM motors. Our Suburban has the 5.3l and it is a great motor. We are at almost 380,000 miles on it.
Either cha-ching, or smart consumers will order their boats with more common engines.
I think the 5.3L had much lower torque than the 350 plus the aluminum block they changed to isn't favorable in a marine environment however as oldjeep pointed out, the 6.0L and 6.2L version of that block have found themselves into boats and are great since they have substantial more torque.I don't know why they didn't just use the new generation of GM motors. Our Suburban has the 5.3l and it is a great motor. We are at almost 380,000 miles on it.
because the 5.3 is a gutless turd? But seriously they are still using the ls3 and lsa
I don't know why they didn't just use the new generation of GM motors. Our Suburban has the 5.3l and it is a great motor. We are at almost 380,000 miles on it.
because the 5.3 is a gutless turd? But seriously they are still using the ls3 and lsa
While I agree that higher peak torque will help plane a heavy boat, the reason it does is because it determines the horsepower at that RPM. Horsepower is ALWAYS what you care about. It takes torque, adds RPM, and voila you have horsepower. No way to calculate speed without it. Torque has no time in the equation, so time is irrelevant i.e. speed. Yes if you have RPM you can calculate something with torque, but then what you have is horsepower. Sounds like a circular argument, but it isn't. RPM adds time to torque so then you can cal speed.Has anyone else wondered- Why don't they post torque specs? Boats run on torque and HP really isn't a necessary determinant of performance when you have a large load to get moving/ plane out with.
Our burb is our tow vehicle. It is far from a gutless turd. Let me know when your dodge hits 380,000 miles.because the 5.3 is a gutless turd? But seriously they are still using the ls3 and lsa
While I agree that higher peak torque will help plane a heavy boat, the reason it does is because it determines the horsepower at that RPM. Horsepower is ALWAYS what you care about. It takes torque, adds RPM, and voila you have horsepower. No way to calculate speed without it. Torque has no time in the equation, so time is irrelevant i.e. speed. Yes if you have RPM you can calculate something with torque, but then what you have is horsepower. Sounds like a circular argument, but it isn't. RPM adds time to torque so then you can cal speed.
Thus the reason they don't publish torque specs, what would you do with it? The only value in publishing torque specs would be to evaluate one power plant against another for planing. It would tell you nothing about top speed though. And, the only way the comparison would be valid would be if the RPM for peak torque would be the same for those two engines. If the WOT RPM was different it would also invalidate the torque spec because you would have to prop differently and change the RPM that was critical for planing. Or if gear ratio was different it would also invalidate the comparison. Ultimately it is torque and RPM at the propshaft that you care about. And if you have RPM then you are dealing with horsepower... If I have a 500 lb ft engine with a 2:1 gear ratio, I have 1000 lb ft at the propshaft. If I have a 1.5:1 ratio I only have 750. Which boat pulls harder? Which engine is stronger? Oh yeah, same engine
The one constant that will still allow you to calculate speed is horsepower. Then you build gear ratio and prop around that. Certainly not the torque spec.
Yeah, this isn't actually the "first" non GM block Mercruiser has used.
They used Ford blocks quite often back in the 70s-80s.
Also, they made their own 4 cylinder back in the 70s-80s also.
So much for inexpensive universal parts. A completely custom new engine will inevitably have more expensive parts than engines used in millions of boats, cars and trucks over the years.
But that is the cost of progress. On paper the specs of this engine actually look very promising.
Volvo Penta already has 350hp,380hp and 430hp versions of the (l96) 6.0l. I'm not sure where a 5.3 would fit into that (also GM has yet to marinize a 5.3l). If the 5.7 is being dropped however, It may be a good substitute for the 300hp range.
While I agree that higher peak torque will help plane a heavy boat, the reason it does is because it determines the horsepower at that RPM. Horsepower is ALWAYS what you care about. ....
GM does not marinize the engines. They just make the blocks and supply them