Mercury 2.5 race

David B

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Does anyone know much about these motors. It came factory with a 3.0 liter mid and lower unit. What is the hp and max rpm and what do they weight. Would this work on a xb2002
 

RiverRat71

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Does anyone know much about these motors. It came factory with a 3.0 liter mid and lower unit. What is the hp and max rpm and what do they weight. Would this work on a xb2002
2.5XS? I have a 2005 2.5XS made by Merc Racing on my GS. It is listed as 225HP & weighs 450lb. It is an Optimax engine with max rpm of 6800. Not sure if 6800 is the soft limit. I was told that these motors were only made in 05 but were quite strong & actually dyno'ed around 240. Mine runs well & feels really strong in mid range. I am confident it will eventually push my rig well into the 90's (still learning).The only drawback as far as I see it is the extra weight from having the 3.0 mid & lower. RR
 

RiverRat71

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I would think the XB02 would be considerably faster than a GS with the 2.5XS but I don't know if it exceeds the recommended weight limit that Allison specs for the XB. Maybe someone with more knowledge will weigh in. RR
 

dubmoney

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based upon the reading I have done everyday for the last 6 years. And my experience setting up my own Allison. I think Darris Allison would want the lightest engine possible on his boats. The xb02 was and is predominately rigged with a 2.5 mercury. The 2005 200xs is slightly heavier, and my cause Darris to issue caution. That being said there are people who have run substantially heavier motors and will report good results. in my very humble and limited experience and I think a 2005 200xs would be just fine on a xb2002. I would run it tune it and work on set-up and would bet that it would achieve every thing you ever wanted without any draw backs.
 

David B

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I have been looking a motor weights and from what I see its only 40 pounds heavier than a 280 with a 20 inch offshore. I was hoping to hear if someone has tried this set up. Its not the 200xs its the 2.5 xs race with 3.0 mid and 3.0 sportsmaster 450# .For a xb 2002 thanks
 

David B

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I think the crank is splined for 3 liter. Don't matter anyway it's a non ratcheting gear case.
 

Darth VMAX

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I wouldn't hesitate at all to run a 2.5xs on my Xb2002.

Where did you find one? They are super rare as 2005 was their only year. Merc killed it way too quickly
 

David B

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A guy at my buddies boat shop has one that he might sell. It has 30 hours on fresh rebuild. Real clean. I thought you could not use a non ratcheting gear case. Or I would have to change it?
 

Dave Hensley

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I don't think the weight is an issue period. The issue is the 3 liter gearcase. It is larger and will provide more stern lift on an XB2002. I don't think you could bolt a 2.5 set up on a 2.5XS and expect the boat to handle the same way. The 6800 rpm limit is strange for a 2.5. My sources say the 2.5 Optis are limited due to piston concerns.
 

RiverRat71

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I don't think the weight is an issue period. The issue is the 3 liter gearcase. It is larger and will provide more stern lift on an XB2002. I don't think you could bolt a 2.5 set up on a 2.5XS and expect the boat to handle the same way. The 6800 rpm limit is strange for a 2.5. My sources say the 2.5 Optis are limited due to piston concerns.
So the same would apply to my GS? I have been told that props blue printed for Allisons are built with more stern lift. With that being said, should that be reconsidered if running the 3 liter lower? Mine has been coned by JC as well. RR
 

Bobalouie

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I don't think the weight is an issue period. The issue is the 3 liter gearcase. It is larger and will provide more stern lift on an XB2002. I don't think you could bolt a 2.5 set up on a 2.5XS and expect the boat to handle the same way. The 6800 rpm limit is strange for a 2.5. My sources say the 2.5 Optis are limited due to piston concerns.

I thought they were limited due to the compressor, but I may be wrong.
 

Dave Hensley

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I thought they were limited due to the compressor, but I may be wrong.[/QUOTE]

That too but the gen 2 200XS ROS in SST trim has an 8000 rpm limiter and runs a compressor. The pistons, according to someone a lot smarter than me, are not reliable at that rpm for very long.
 

Dave Hensley

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So the same would apply to my GS? I have been told that props blue printed for Allisons are built with more stern lift. With that being said, should that be reconsidered if running the 3 liter lower? Mine has been coned by JC as well. RR
The pencil roll provides stern lift. Stern lift is what gets you in trouble. Real easy to get trim happy when the boat feels like it is flattening out.
 
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