Did a little measuring and math today on our snowthrowers to try and put values to our varied results. Assuming a 4 5/8 pto pulley and 4.5 thrower pulley.
QA42A (H42) - belt=1:1.02, Gearbox=2:1, Chain drive=1.7:1 Total reduction is .2997
So stock 1072 RPM rotor for a 38.5 mph
release (leaving the rotor impeller) speed. Now there are losses for the chute and impeller efficiency. The bend of the chute could be as much as half. And the rotor could only be 80%. Assuming both and not digging up better math. 30mph release for 15mph at the end of the chute.
Mine throws 4-6ft with heavy snow. Barely gets over the side of the blower. Only used once but not expecting much better with light snow.
PTO (worn so belt sit lower) 4 inch & 4 inch thrower pulley.
Total reduction is .2916. Rotor=1050RPM, Release 37.4MPH, 80%=29.9MPH, Chute=14.9MPH.
Now my old HiCast38 that throws anything. Heavy snow better than light. 20ft easy and could do 40. Pretty much the same blower housing as my H42.
Guessing on my PTO as I can't measure it. Between 5.375 and 5.875 inch from searches. So will give both.
5.375 - Rotor=1612RPM. Release=57.5mph, 80%=46mph, Chute=23MPH
5.875 - Rotor=1762RPM. Release=62.9mph, 80%=50.3mph, Chute=25MPH.
Video of the Haban
http://www.youtube.com/watch?v=Exs0eg4l4Ds
http://www.youtube.com/watch?v=45j1q6hCp90
Sorry for the long post