baywatch

The last 41' six pack I was in had four in the bilge and two in front of the helm. When you have to crawl back there underway to switch tanks it would be a little tricky LOL..

tcelano

Is it possible that Merc is sandbagging the rating, and the motor is actually putting out more than 1350?

The speeds some of these 1350 boats are running definitely suggests it.

I'd think if they were running excessively rich, there'd be soot everywhere.

Imagine, if you will, getting a 2.5 gallon jug of gasoline, and pouring it onto a campfire in one minute. That's about 145 gph...

mcollinstn

A buddy has the 1100's in his boat. He swapped out a pair of 2010 1075SCi's for the 2011 1100's. Same boat - same setup - just a motor swap and new outdrives (same drysump 6's, same ratio). And steeper props of course.

Boat went from 147mph after 3 miles with 1075SCi's to 155mph in a shorter distance. And the acceleration is fierce.

It takes more than 25 hp per motor to deliver that sort of speed increase. Either the 1075's were overrated, or the 1100's are underrated.

MC

A.O. Razor

One answer to this, would be because the 1075's were crank rated and the 1100's and 1350's are rated at the tranny.

44MTI

And man does Jimmy test the equipment. He is my hero.

I think the Ratings Merc gives are consistently conservative. At least that is what I have seen. As we all know a 1075 Merc boat is usually faster than anyone elses 1100hp in the same hull.
I think the difference in Jimmys boat, probably in any of them, is the torque curve. The 1100's make alot more torque than the supercharged 1075's, so that would explain the increase in acceleration. As far as top end there a several factors as play, increase in Torque, taller gearing (props) and the torque to turn them, and the higher rev limiters in the 1100's, 6000 vs 6500.
These are just the highlights that jump out and me and the ones Randy was most excited about..
Now Jimmy needs to get a set of 1350's before the shootout. Hope to see you there if not sooner.


Back to the poster question. What we see in most MTI's is about .8-1 MPG in 100-120 mph cruising with 1075's. It drops off ALOT when you start running 140-160ish.
The 1350's are suppose to be more effient then these. So maybe you can use this as a baseline
Michael

Adam Younger

Many thanks for all the details - the design in its various aspects is progressing really well and I'm sure at a suitable stage we will post details - but of course the owner's decision as to when details get released.

Getting close to deciding who will build the boat(s) and a start date - so exciting times.

The boat itself has some pretty different features and whilst speed is of course important it is primarily a Marathon racer for events such as the Cowes -Monte Carlo race in 2013

paul buckner

Well said sir . I have met Adam and he has designed many boats here in the uk NICE GUY . IF ITS PAINFULL TO FILL YOUR BOAT IN THE STATES YOU CAN NEARLY TREBBLE THE COST HERE IN THE UK . FROM WOT MY PALS TELL ME , I CHANGE COLOUR AT THE GAS PUMP . I THINK ADAM IS TRYING TO GET AS MUCH IMFORMATION FROM WHEREVER HE CAN.

mcollinstn

And you're no wimp either. Seen you run balls out through the same kind of congested traffic and such as well.

Torque is certainly the main attraction on these turbo 4-valvers. Rev limit, though, is set lower (factory) on Jimmy's 1100's than it was on his 1075's (ECU tweak). With the 1075's, Jimmy tried tall props once, and there wasn't enough lake to get it stretched out and acceleration suffered.

Bottom line is these new turbo motors and the 4 valve heads are like having cake and eating it too. With a one year warranty no less.

MC

mcollinstn

Sure, that's some of it, but we're talking about a HUGE performance difference. If the 1075SCI was only 1025 net crank hp (w accessories driven), and if it took another 25 hp to go towards running the transmission pump and the additional parasitic drag, then we're looking at a minimum net transmisison hp of 1000 for the 1075.

Let's go even further and say that the 1075 SCI is only good for 975 hp.

The 100hp increase (from the 975hp 1075 SCI to the Merc 1100) would STILL not account for the performance difference between the motors.

Never have I heard of a 10% hp increase delivering the kind of night and day difference these things give.

If the 1350 burns 145 gallons per hour, then my guess is that the hp is higher than rated as opposed to the BSFC being higher than expected.

MC

40gt

Twin 1350s - fuel consumption?
I'm thinking around 100 gph each at 100mph in the M31DCB from memory, but I could be wrong.
But that could have been total, not sure.

What I do remember is we stopped for fuel twice , put in a total of $1,500 for about 4 1/2 hours of cruising.
No I cannot remember what the price of the fuel was.
Mind you, a lot of our cruising was done at 112 -125 mph.

If you can picture this speedo movie in reverse in your head, that's about how quick your fuel tanks go down running the 1350's!
This is not a full speed run, just a short staged up blast.
It wasn't our boat so we didn't want to abuse it.

But worth every cent IMHO.
Who said you can't buy happiness?