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GreenSpirit Hydro
02-19-2008, 01:16 PM
I have on 07 X-star ss w/ the stock prop. I got the boat in late October and only took it out 4-5 times before the water got to cold. However, I couldn't believe how fast I was running through a full tank of gas. Would a different prop help conserve gas? What does a different prop do different fro the boat? Any other ways to conserve gas?

88 PS190
02-19-2008, 01:31 PM
simply you can select a prop that will lower your rpm at speed. But this same prop will make it slower out of the hole.

If you are say into cruising that could make sense, if you are a wakeboarder and you are frequently pulling riders up and looping back when they fall you will not save fuel, and it will be a poor ride for the guy you drag around back there getting to speed etc.

To save fuel minimize the amount of time spent off plane, empty ballast when not boarding. Get a new prop, because the boat will hook up better, there is a thread currently going on about this same subject. Get a fuel consumption gauge and you can watch your gallon/hour use rate.

tex
02-19-2008, 01:42 PM
Spend more time floating and drinking beer!

coz
02-19-2008, 01:54 PM
I have on 07 X-star ss w/ the stock prop. I got the boat in late October and only took it out 4-5 times before the water got to cold. However, I couldn't believe how fast I was running through a full tank of gas. Would a different prop help conserve gas? What does a different prop do different fro the boat? Any other ways to conserve gas?

4200lbs dry is alot of weight to push through the water and add all your goodies and your over 5000lbs. A new prop isn't going to give you that much gas saving. It's a big boat with a big appetite.

88 PS190
02-19-2008, 01:55 PM
here's a thread just a few down on the page, talking about he MCX engine and stock prop, with mention of which aftermarket prop to run.

Wake boats will never get the fuel economy as V-Hull Inboard outboards, which go faster with less fuel consumption, but will never work so well for you while boarding.

stuartmcnair
02-19-2008, 01:57 PM
if gas was going to be a concern I would have never bought a boat with a big V8 in it

Sodar
02-19-2008, 02:19 PM
I have on 07 X-star ss w/ the stock prop. I got the boat in late October and only took it out 4-5 times before the water got to cold. However, I couldn't believe how fast I was running through a full tank of gas. Would a different prop help conserve gas? What does a different prop do different fro the boat? Any other ways to conserve gas?

Call Eric @ OJ Props or Bill @ Acme Props. They know about this stuff and will lend you different props to try out.

stuartmcnair
02-19-2008, 02:27 PM
my post was meant as more of a "pontoon boats with a 90 HP Honda get great mileage...but boring as hell"

ridesdirt
02-19-2008, 02:38 PM
MYMC can hook you up with what you want. Talk to Mike, he has tried a lot of props on the X-Star.

My '07 MCX X-Star has OJ 14.25x14 XMP Edge. From my research it is the prop to have with your setup.

Leroy
02-19-2008, 02:43 PM
Normally boats are measured in gallons of gas used per hour. How about a number, gallon of gas you bought and hours on the boat?

I have on 07 X-star ss w/ the stock prop. I got the boat in late October and only took it out 4-5 times before the water got to cold. However, I couldn't believe how fast I was running through a full tank of gas. Would a different prop help conserve gas? What does a different prop do different fro the boat? Any other ways to conserve gas?

GreenSpirit Hydro
02-19-2008, 03:01 PM
My x-star holds 55 gals of gas. It seems like we run through it in 4-5 hours. We usually run about 40mph to get to a good spot to ride (maybe 15-20 minute boat drive), then ride at 22mph. It seems like my friends Malibu can go all day on a tank of gas w/ a boat load of peeps. I have never had more than 4 in mine at a time. Just hoping I could find some way to conserve.

88 PS190
02-19-2008, 03:18 PM
how many rpm is 40 mph in your boat? Seems like that is pretty well redlined out, and of course will result in poor fuel economy, its like pegging a car to the rev limit up hill for 20 minutes.

are these malibu's large wake boats or smaller multipurpose wake/ski and direct drive?

coz
02-19-2008, 03:51 PM
My x-star holds 55 gals of gas. It seems like we run through it in 4-5 hours. We usually run about 40mph to get to a good spot to ride (maybe 15-20 minute boat drive), then ride at 22mph. It seems like my friends Malibu can go all day on a tank of gas w/ a boat load of peeps. I have never had more than 4 in mine at a time. Just hoping I could find some way to conserve.


You'll get better gas milage running at 40mph on plane than pulling a boarder at 22mph but i'm sure that's not why you got the boat. I have the 5.7 Vortec MX EFI 300hp and my fuel pump volume is 1 pint per 20 seconds and when you look at it like that it hurts. My last boat had a v6 with a mercruiser and I could play all weekend on a tank, not my MC, but it's definetly worth it for every penny of gas I put in it. :D

brat
02-19-2008, 04:14 PM
Spend more time floating and drinking beer!



Tex, you are a man after my own heart. I couldn't have said it any better.:cool:

ttu
02-19-2008, 04:16 PM
Tex, you are a man after my own heart. I couldn't have said it any better.:cool:

i always wondered why i got 2 weekends out of a tank of gas.:rolleyes:

MYMC
02-19-2008, 04:30 PM
You'll get better gas milage running at 40mph on plane than pulling a boarder at 22mph :D
Wanna bet a year's supply of fuel on that?:confused:

MYMC
02-19-2008, 04:39 PM
My x-star holds 55 gals of gas. It seems like we run through it in 4-5 hours. We usually run about 40mph to get to a good spot to ride (maybe 15-20 minute boat drive), then ride at 22mph. It seems like my friends Malibu can go all day on a tank of gas w/ a boat load of peeps. I have never had more than 4 in mine at a time. Just hoping I could find some way to conserve.
As I have explained several times...fuel burn is a function of horsepower...which is equal to RPMxtorque output/5252. It takes approximately .50lbs of fuel per hour pre horsepower in a boat...so do the math. The greater the RPM the greater the horsepower (until the peak) the greater the fuel burn. Yes this is a overly simplistic view. You could have a 14.5x22 prop, an RTP engine and 3000lbs of ballast and the equation won't work because you are just fuel washing the cylinders. But in a "real world" application the above information will do everything you need.

Larger props will cause you to use greater throttle angles at lower speeds and small props will cause you to use less...all too a point. Without a fuel flow turbine there is no hard answer just trial and error.

What engine do you have?

Also the “run” to your ride spot is where you are burning up your fuel. I imagine RPM is nearing 5000 at this point?

drylandfish
02-19-2008, 05:22 PM
Listen to Tex. He seems to know what he's talking about. :toast:

Leroy
02-19-2008, 05:41 PM
So with your numbers if I assume 50 gal and 5 hours that is about 10GPH, probably not out of line for that size boat and engine.

I looked for a graph of GPH vs speed and that would tell much of the story but could not find one. Normally the GPH is lowest between about 15-30MPH and normally doubling at near max speed. My 230 gets about 5GPH, but I cruise at 30 and it is lighter and probably smaller engine (LTR1 330HP).

Other than the prop, try cruising around 30MPH to the good spot. I wouldn't expect the prop to give you a lot.

My x-star holds 55 gals of gas. It seems like we run through it in 4-5 hours. We usually run about 40mph to get to a good spot to ride (maybe 15-20 minute boat drive), then ride at 22mph. It seems like my friends Malibu can go all day on a tank of gas w/ a boat load of peeps. I have never had more than 4 in mine at a time. Just hoping I could find some way to conserve.