Identifying year and hp for a Lower unit 2.3 ratio

[Chinpoker]

Hi y'all looking for some info to identifying the year and hp of a 2.3 gear ratio L/U that I have mounted to a 64' 850 straight 6 as I'm looking to fit the right size from prop Propulse?

As the guy who sold the L/U to me doesn't remember what year/hp motor it came off of
Any help is greatly appreciated!

 

[Chinpoker]

Even just a location of a part # stamp would be great thanks again!

 

[Chris1956]

The inline 4 motors from the 70s had that gear ratio. Not sure why you would need that info. A choice of prop pitch and hub size (likely 4-1/4") should be all the info you need.

 

[jimmbo]

The 4 cylinder 65, 75, 80, and 85hp engines used the 2.3:1 case. If used on an in-line 6 the the prop would need to be about 2” higher in pitch than a the original ratio, usualy 2:1 or something close
Your engine has max rpm range 4800 - 5300

 

[Chinpoker]

The 4 cylinder 65, 75, 80, and 85hp engines used the 2.3:1 case. If used on an in-line 6 the the prop would need to be about 2” higher in pitch than a the original ratio, usualy 2:1 or something close
Your engine has max rpm range 4800 - 5300

Thanks Jimmbo great info helps me out a lot!

Thank you Chris!