Which motor?

[bryan28]

I'm considering a SeaArk 2072 vfx. The hull weighs 1250 lbs, it has a 15* deadrise, is 20' long and has a 94" beam. It is rated for up to 175 hp but money is a factor. Would a Mercury 115 Pro Xs command thrust or a Suzuki 140 be a better choice? I've read that they both produce 126 hp. Hard to believe a motor rated for 140 hp only produces 126 hp. Thanks

 

[beetlespin]

I'm considering a SeaArk 2072 vfx. The hull weighs 1250 lbs, it has a 15* deadrise, is 20' long and has a 94" beam. It is rated for up to 175 hp but money is a factor. Would a Mercury 115 Pro Xs command thrust or a Suzuki 140 be a better choice? I've read that they both produce 126 hp. Hard to believe a motor rated for 140 hp only produces 126 hp. Thanks

I have a 50hp Mercury on my Grizzly 1860 and it will do 25mph all day long sipping gas. If I push it I can get 30mph.

 

[nccatfisher]

I have a 115 yamaha on a 2472 SeaArk and it does a fine job.

 

[Pappy]

Flip a coin..................or go with the engine that has the best servicing dealers in the area to back you up should you need help.

The Merc comes with a choice of gearcases. For a normal application I would choose the larger unit simply because it will swing larger blades and carry the boat better at mid-range RPM.

They both turn within 100RPM of each other and they both perform about the same. Testing by magazine and by Merc as well indicate that the new version is only worth about 1mph over the standard version. That extra mph appears to be realized by the utilization of the smaller gearcase. If that is the case then the standard 115 would be my choice as you will be running the boat at cruise 90% or more of the time you are on the water and the larger gearcase will do the best job.
You can gain better speed by sending your prop off to Mazco or someone and come out money ahead.

Just my .02.

 

[bryan28]

I think I've decided when I'm ready to make the purchase I'm going with the 115 Pro XS with command thrust (2.38:1 gear ratio). It should put me in the mid-40mph range. Plus, being able to run a larger prop should give better acceleration and, as Pappy said, carry the boat better at mid-range cruising rpm's.

 

[Pappy]

Do a bit more research.
What they did was up the rev limiter on that engine by 300 rpm. In doing so this almost forces you to go down one pitch in prop to reach top RPM. This was done on purpose to get the little bit of extra horsepower and to give better acceleration. They did no internal changes to the engine to increase bottom end horsepower.
From what I read the acceleration comes from going down one prop size. Not a good trade off for mid range cruise.
Would go search boat tests that use both versions of the engine and study mid range specs. Think you will find the standard engine turning the higher pitch prop will be more efficient.

 

[Shaugh]

I agree with Pappy, a decision like that for me would be 100% about service and reliability. The performance difference would be nothing compared to the performance of which one spent more time in the shop.

 

[beetlespin]

I think I've decided when I'm ready to make the purchase I'm going with the 115 Pro XS with command thrust (2.38:1 gear ratio). It should put me in the mid-40mph range. Plus, being able to run a larger prop should give better acceleration and, as Pappy said, carry the boat better at mid-range cruising rpm's.

Good choice. From what I read these motors are awesome.