I am in the process of tuning our torsen diff. and i was wondering if anyone can tell me how to measure the torque bias ratio, and secondly how to tune it. We have a type 1 zexel.

we have been brainstorming on how to test the bias ratio but havent come up with anything yet. However to change/tune the bias ratio you can play with the pitch of the gear teeth(costly and hard to do). Simpler ways include playing with different viscosity lubricants, and the washers in between the gears can be replaced and modified to get different friction coefficients. if you think of a way to test the ratio let me know

Are you using the University Special? If you are, the bias ratio is 3.2:1 before break-in and 2.6:1 after break-in according to Torsen's website. If it is another model, you can probably contact Torsen and get the info you want. There is also a Formula SAE FAQ on the site that discusses, among other things, how to modify the bias ratio

Zexel Torsen Home Page

P.S. What's up Tal

Lehigh Formula SAE

www.lehigh.edu/~insae/formula