Hello, I am new to the forums (been reading them for a while). I have recently acquired a JLO Rockwell 340cc 2-cyl 2-stroke snowmobile engine, torque converter and final drive for making a mud motor. The engine has 26 hp and 21.6 lb-ft at 6250 rpm and after the torque converter the final ratio is 3.91:1. It has a Tillotson HD diaphram type carb and weighs 62 lbs (minus torque conv. and sprockets).

I was hoping to get some input on the prop diameter and pitch and length of the prop shaft. Has anyone out there had experience with a 2 stroke in this type of application?

Sounds like after gear reduction you will turn prop
at a similar rpm to the crawfish models like the GoDevil...

Maybe starting with a prop like theirs would be a good starting point...
A 10x9 or 10x11 I believe...

Not sure if many have seen or tried the 2 stroke w/reduction...

Thanks for the input Gigafowl. I know I can't match the brute torque of a big block 4 stroke, but in snowmobiles they run through a chain case for gear reduction. Otherwise the track would be spinning at the same insane rpm as the second pulley in the clutch and making no torque. An older sled with this 340cc motor and gear reduction would go about 50 mph.

Anyone out there ever see a 4 blade mud prop?