I forgot to mention the Bell is 3:1.

     The Allison version will be in the same ball park.

     BTW rumour has it the new RXx will be 3.2 litres equivalent so at
     the same level of tune as the current 13B  TTC engine we are looking
     at 800 HP for a two rotor. It is all aluminium stock as well.


     Paul Lamar


     Paul, you might look at the gear set from a NP241 transfer case,
     it's very beefy and it doesn't have a lot of crap attached to it.
     Ratio is 2.72:1.

     Everett Rankin

     How much torque is it good for?

     Paul Lamar


    Supposedly 5500 lb-ft, like I said, it's beefy;)



http://www.genuinegmparts.com/pdf/powertrain/GM%20Parts%20Remanufactured%20Transfer%20Case%20Specification%20Chart.pdf

    Everett Rankin


    I doubt that. I think you mean 550 ft pounds.
    The ratio is too low for rotary use. We need 3;1 minimum.

    The Ford is good for 650 ft pounds and is used in the power stroke
    diesel. It is also 3.12 to one.


    Paul Lamar

The chart reads 5000 lb ft. The input to the transfer case is the engine
torque x torque converter x first gear ratio. The other thought with
regard to this is the fact that low range used in a transfer case is
designed only for short term intermittent use.
When you go to the Allison MD 3060 transmission, the first gear is
designed for 900 lb ft input torque and use in cement mixers etc. for
use around town. Heavy loads and lots of red lights. In the specifications
there is a maximum RPM input listed. That more pertains to the torque
converter than to any other component. An advantage to the Allisons
is that many of the planet carriers are rebuildable with planet gear kits.
If they survive construction sites in trucks and other equipment in mud and
God only knows what else, they will work real well as an aircraft PSRU.

Dale Davies

Must be for some sort of truck. The weight is 75 to 100 pounds. Totally
out of the ball park for our applications. The Ford planet set weighs 8 pounds.

The complete Bell 47 Gear box is only about 45 pounds. About the same as a Tracy.
And that is a monster planetary.

Paul Lamar

     The Rotary Engine News Letter. Powered by Linux. If you want off the
      list PLEASE let me know and I will remove  you.  ACRE NL web site.
     http://www.rotaryeng.net You Tube http://tinyurl.com/beqqxas
     Copyright 1998-2016 All world wide rights reserved.