Is the differential for the AWD in the Evo a 50/50 split all the time or is it variable? Thanks!

 

50/50

 

Center diff is viscous type set up for 50/50 all the time.

 

No thats not right ....viscous will allow more torque/drive to be distributed to the the front/ rear as needed....up to sort of 70/30 either way.....it is not 50/50 regardless of the grip available on one axle

 

Okay...now we have a debate...does anyone have DATA to back up their answer, please?

 

straight from 's site


Full-Time All-Wheel Drive with 50/50 Viscous Coupled, Center Differential, Front Open-Type Differential and a Rear Mechanical Limited-Slip Differential.

 

It is 50:50 if there is no slipping (usually happens on dry tarmac without too much load) present. Once you go WOT, slip starts to happen and for a while you get something close to the 50:50, but rarely exactly that. And more of the power goes on the side where you have less grip. Viscous unit is just trying to bring that to as little as possible, but it never gets there.


Fedja

 

50:50 with no slip...

but will vary based on slippage.
for example on a launch, the front wheels will slip more cause of all the weight transfered to the rear, in which case you may see a 30:70... as far as I remember about viscous diff. it can vary to close to 10:90, maybe even more.

Meaning your front wheels are off the ground, and close to all the power will be transfered to the rear.

 

It isn't a viscous diff!

The differential is open. It gives a 50/50 torque split when there is no slippage.

The viscous coupler connects the two axles in the differential. When the two axles turn at different speeds (slippage between the front and rear axles), the plates in the viscous coupler shear the fluid between them. This shearing heats up the liquid, and it turns to putty. The putty is thick enough that it tries to lock the two differential shafts so they turn at the same speed (50/50 locked). In reality, it never locks them together 100%, and the end of the car with less traction will get slightly more torque than the other end.

 

Actually a viscous diff locks with plates that contact eachother. The fluid in the differential acts like a lubricant between the plates. When there is a difference in speed between the two output sides of the differential the plates start spinning at different speeds. That heats up the fluid and it actually thins it out allowing the plates to contact eachother. That contact in theory creates enough friction to lock the differential.

I've gotten into arguements over how a viscous diff will transfer power with MrAWD before. Don't want to make it a huge arguement again because there's no getting through to him. Just wanted to give my "correct" view. Yes the diff is set up to split an even 50/50 under normal driving. When one side starts to slip though, the diff starts to lock up. The side slipping does not have the traction to put the power to the ground. So the diff locks up and turns each output at equal speeds. Equal speed doesn't mean equal power, the slipping side has no traction so it just spins and most of the power actually goes to the ground on the side with traction.

 

Hey old friend!! Remember me?
Few things I have to add here, tough. Fluid in the diff has nothing to do with the fluid in the VC, which is completely sealed.
Then, plates never touch each other and there is no force created due to the their contact. There is a force that is created between the two objects, when fluid flows between them. More speed, more force. And that force tries to bring those two objects together. The best example would be two boats on the river that would hit each other if they get close enough for the force to have an effect.

In the VC case, there are plates on the both sides of each plate in side (except the outside two) and that one is keeping them in the middle all the time and no touching is allowed (sorry ).

I believe that we where on the same page here


As usual, here is a on me!


Fedja

 

So...this mean it is a 50/50 split, but when you are diving into a wet corner it will vary from that and is not 50/50 all the time?

 

O well i thought it was 50:50 all the time.. guess i was wrong..

 

ShapeGSX

viscous diff. or viscous coupling is the same thing.

Its the wheel with less traction side that causes the liquid to turn to puddy...in which case locks up and more power is now sent to the wheels with traction...

I believe Ben and Mr. AWD are on the same page as me... same speed does not = same torque.

 

I've held a DSM viscous coupler in my hand. I've also held a DSM center differential in my hand. They are two separate components. The differential is open. The viscous coupler modifies its operation. It is not a viscous differential. Hell, I don't even know if such a thing exists.

This is the same way the Evo does it.