Mercury XR Black Max series

[utfyrfytr]

Just a curiosity thing but, can anyone tell me what the XR stands for in the Mercury XR Black Max series of motors? Thanks

 

[racerone]

I believe XR motors produced more power than what the decal on the cowling says

 

[utfyrfytr]

I am really not knowledgeable about this motor but, I have a friend who has a Mercury XR 2 150hp Black Max and he was asking. 150hp is all that I am aware of ( there may be others) but I do know they have XR 2, 4, 6 and 8 and I don't know what any of that means either. Thanks for the thoughts.

 

[Faztbullet]

Xr2 150 was stock 2L 150 with 200hp divider plate and spark advance box 2:1 gear ratio......made about 160hp
Xr4 150 was a 2.4 with vertical reeds with a inline lower unit with 1:78 ratio.........about 170hp
Xr6 150 is a 2.5L with inline gearcase 1:78 ratio..........about 175hp

 

[utfyrfytr]

Interesting stuff. I wonder why they didn't rate them at their actual horse power? So does anyone know what if anything the letters XR actually stood for?

 

[Dukedog]

XR series was mainly developed (badged) with a few differences like above for tha bass trail when it was limited to "production rating" of 150 hp ..

​jan... actual hp is a crap shoot with "production" motors anyway......... some do and some don't... besides tha XR makes for a cool "marketing" decal!

 

[jimmbo]

The XR2 series, did produce power at the higher end of the 10% tolerance, mercury engines almost always did that. The XR2 really didn't put out any more peak hp than the the standard 150, but it made more power in the midrange to help get boats in its intended market get on plane quicker.

 

[utfyrfytr]

Thanks for all of the great info.