transmission capacity thumb rule
transmission capacity thumb rule
(OP)
On another group someone mentioned "As a rule of thumb a transmission with the shaft spacing of the Corvair (77mm) is not good for more than 300 lb*ft."
Is there a more complete general rule for trans capacity?
Thanks,
Dan T
Is there a more complete general rule for trans capacity?
Thanks,
Dan T





RE: transmission capacity thumb rule
Is there a more complete general rule for trans capacity?
Yes, the original manufacturer's rated torque capacity.
There is much more to a transmission than a input shaft.
RE: transmission capacity thumb rule
ISZ
RE: transmission capacity thumb rule
RE: transmission capacity thumb rule
RE: transmission capacity thumb rule
He referred to it as the "Chrysler formula" but I have found no reference other that that conversation to such formula.
It stands to reason that in a given center distance you are limited by the torque you can transmit. The center distance will dictate the size of shafts, bearings and gears. While it is true that you can increase the face width of the gear to carry more load or increase its durability, doing so will change the bearing center distance (on the same shaft) and thus will increase the shaft deflection and consequently limit the benefit of the increase in face width.
I know the fellow has retired but I will try to get in contact with him to get the "Chrysler formula".
RE: transmission capacity thumb rule
thanks,
Dan Timberlake
RE: transmission capacity thumb rule
The design rule of thumb I mentioned before is as follows:
Shafts Center distance [mm] = 30 x (torque [kgm])^(1/3)
This is from the older fellow I met years ago that designed most of Iveco truck transmissions.
RE: transmission capacity thumb rule
Rod