Mercury 300XS

[gar163y]

Quote from Alan Stoker of John's Custom Marine about the new and much heralded Merc 300XS: ............"The biggest gain (over the 300X) would be in fuel economy as the 300XS is a direct fuel-injected engine and not a standard EFI. This system allows for fuel to be injected after the exhaust port has been shut; with the exhaust shut incoming fuel does not escape. Other gains will be an engine that idles better and meets the new emission standards set forth by our (the US) government. The engine has a lower-rated maximum rpm, so I would not expect much of a top-end performance gain, the longer stroke will help to overcome the need to run a larger propeller. DFI engines generally accelerate better and I would expect that to hold true for the XS, again the added stroke would help. In the end I would expect similar performance numbers on a medium sized boat, but better as the size goes up (increased torque). I would in turn expect a 300X to perform better on a light small boat due to its increased rpm capacity." .................John Stoker produces Stoker boats and is a multi time Mod VP champion. This motor has been talked about for some time as if it was the Holy Grail and yet perhaps it just might not be.

[Matt]

I think it looks pretty good overall. There are a couple of drawbacks I've seen though:
They've fitted a dustbin for a cowl.
Needs high octane fuel.

[Matt]

P.S. I know the "X" does too, and more of it, so it's no worse than the offering it replaces.

[kiwiracer]

i think we are witnessing the demise of the high revving performance motors
my opinion on the XS has been the same as John Stokers, gains on the X everywhere except when used in a pure performance application, tip speed is what we need to make our boats go, not slower revving motors trying to swing big props
anyone agree?

[BluFin]

Lets see what model year 2008 brings possible late 2007. I hear they are being a little more creative with 2.5 ish cc's

[kiwiracer]

what we are hearing down here is that Mercury are doing something with th four cylinder verado

[Matt]

And also the demise of the engine crane to change motors after each race.

IMVHO the larger capacities we're seeing are a step forward, and while they have a higher initial outlay the longevity, in race terms, should be improved. The motors don't rev their nuts off now, (Johnrudes never did), yuo can still bring the propshaft rpm back up with gearbox choice.

You can't just let the fkkr "bark" now cos the electronics control it.

The main boats that appear to lose are the ultralight boats where the weight increase or balance change is significant. But give it a couple of years and people will have em ironed out again.

So yeh, I think you're right, but I also don't think it'll be a big deal once we're down the evolution path a bit more. Ultimately, people are still learning how to make the best of these motors.

Originally posted by kiwiracer
i think we are witnessing the demise of the high revving performance motors
my opinion on the XS has been the same as John Stokers, gains on the X everywhere except when used in a pure performance application, tip speed is what we need to make our boats go, not slower revving motors trying to swing big props
anyone agree?

[BluFin]

Originally posted by kiwiracer
what we are hearing down here is that Mercury are doing something with th four cylinder verado

Yep sure are Converting it for use as an agricultural pump to move slurry and other shite and going back to proper two stokes ………………2008 will be a key year as to the direction

[Matt]

Mark in the book for another blufin prediction...

[BluFin]

What like the 300XS 7 months before it was announced by Merc

http://boatmad.com/forum/showthread....ighlight=300xs
or thread
http://boatmad.com/forum/showthread....ighlight=300XS


two stokes are coming back for one last run

[Matt]

So what, specifically, is coming.

[BluFin]

I'll rub my crystal balls ah yes yes yes.......... the mist is clearing
Guessing by the new personel some forced induction possibly.
revamped 2.5 around 2.8 pushing around 310Hp race versions only. an increase in the 300xs moving up to 350 but still offering the 300 as well.........oh the mist is returning it's getting foggy will have to rub me balls again

[cfun]

A couple of years back used to chat to a usa marine guy who had a shop just down the road from Mercury, a couple of is mates worked there, he told me they had been experimenting with a race verado it had produced over 500+hp but it was unreliable, but they would do one around 400ish most poss?????? I wonder if this is still on the go, as if so that should be the next race class, and could do away with 4ltr and 6ltr with single and doube engine installations

[Adam]

Was talking to a dealer abroad who went to collect smoe new Verados - apparently they are all identical when they arrive and only have ECU's and decals fitted when it is decided which model is being ordered.

This is all very well - until you look at the different prices for the different powers from what is really the same engine.

[Matt]

[BluFin]

Oh I forgot about about an alternate fuelled model dont know the max output though

[Matt]

That's already available.
Run's on everything (petrol, diesel, A1 etc)

[Jon Fuller]

Originally posted by Adam
This is all very well - until you look at the different prices for the different powers from what is really the same engine.

Yeah, but to be slightly fairer, some of the extra cost will be to cover the higher risk of failure in the larger power variants, and it's associated warranty needs.

[verytricky]

So you could buy the lower 'powered' version, get it 100% balanced to handle the extra stresses, then chip it up? Getting a more reliable higher HP engine for less?

[1up]

Originally posted by verytricky
So you could buy the lower 'powered' version, get it 100% balanced to handle the extra stresses, then chip it up? Getting a more reliable higher HP engine for less?

as far as i've been told by a mercury dealer, the price of th ecu is vitually the difference in the price of the variance of the same engine.