Locked center diff...
06-08-2005, 03:50 PM
#12
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you are thinking locked rear or fronts, i have street driven a spooled car and truck, not that bad
the center diff wont cause that, the diffs in the front and rear still allow the inside tire to move slower in a turn thus eliminating any bind that could happed...
but then again i would assume that you would know that and simply read my post wrong
but then again i would assume that you would know that and simply read my post wrong
06-08-2005, 04:03 PM
#13
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Becuase I am not convinced it is needed or works that way and that 50/50 would be better.
Enlighten me if I am ill in my thinking, I am no master of this stuff and would be more than interested in your constructive criticism of my idea. After driving cars with a setup that is similar in what I want to accomplish with this I think that it would help in many track situations. I was under the impression that the center diff simply dictates how much power goes to the front or the rear. Stock it gives approx. 60 rear, 40 front and then with a product such as the Stasis center diff or the OEM rs4 diff it gives approx. 80 rear, 20 front. Am I wrong?
06-08-2005, 04:09 PM
#14
I have. I had an 87 Cherokee 4.0l and a 94 Wrangler 4.0l...
...and have driven them locked at in parking lots.
Not fun.
But locking the center at a 50/50 split will not cuase that type of side to side lock wheel chirp/hop that's caused by locking the front or rear axel.
Not fun.
But locking the center at a 50/50 split will not cuase that type of side to side lock wheel chirp/hop that's caused by locking the front or rear axel.
06-08-2005, 04:14 PM
#15
you are correct, but with our Torsen, you can't specify a static torque split...
...only the torque bias ratio (or multiplicative factor).
So stock is 2:1, stasis is 4 or 5 :1. But with no traction issues, it's still like 50/50-ish.
Not exactly, as it's dynamic.
A viscous is waiting for slip front vs. rear so it can start to redistribute torque. Before any slip, it has a static bias (50/50 or 20/80 or whatever).
The Torsen will just move torque around all the time, but given that the car is sitting at a 60/40 weight split, I'm guessing in cruise with no traction issues, the Torsen is distributing between 60/40 to 50/50 or there-abouts.
So a locked torsen center should really not drive any different until you encounter traction issues, and I'm guessing that a locked center at 50/50 will have more front wheel spin then a car with a stock 2:1 center Torsen.
I could be wrong though...
So stock is 2:1, stasis is 4 or 5 :1. But with no traction issues, it's still like 50/50-ish.
Not exactly, as it's dynamic.
A viscous is waiting for slip front vs. rear so it can start to redistribute torque. Before any slip, it has a static bias (50/50 or 20/80 or whatever).
The Torsen will just move torque around all the time, but given that the car is sitting at a 60/40 weight split, I'm guessing in cruise with no traction issues, the Torsen is distributing between 60/40 to 50/50 or there-abouts.
So a locked torsen center should really not drive any different until you encounter traction issues, and I'm guessing that a locked center at 50/50 will have more front wheel spin then a car with a stock 2:1 center Torsen.
I could be wrong though...
06-08-2005, 06:40 PM
#18
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Having driven true 50/50 split AWD cars, I think the S4 benefits from rear torque bias. [more]
To effectively "couple" the power from the front to the rear in a B5 S4 would not be ideal. I think you would find that the performance capcity would be best with a rear bias (more RWD) power configuration.
Just a thought, but I think a true 50/50 torque split in an S4 would produce a lot of high slip angle understeer in the front. It's possible to calc some of this out in terms of vehicle dynamics, but more effective if one actually tested on the race track at combat speed.
Just a thought, but I think a true 50/50 torque split in an S4 would produce a lot of high slip angle understeer in the front. It's possible to calc some of this out in terms of vehicle dynamics, but more effective if one actually tested on the race track at combat speed.
06-08-2005, 06:48 PM
#19
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thanks for the input, this might be one of those things i will put off until i find another center
diff and then do a 2 day track event, that way i can have back to back days on the same track with all other variables being the same to see how it is. i agree on the front probably being more spin happy then it already is, but tires can be changed to deal with that.
