tarmac/gravel/snow

[krucial]

so does any of the ACD settings allow more than 50% torque distributed to the REAR?

[HoLeeRay]

no

[HoLeeRay]

i'm actually interested in knowing if the gravel/snow modes give better power to the ground when racing from a roll. i'll try it this weekend, maybe there is a difference?

[propellerhead]

I'd be interested to hear what the tarmac setting actually delivers to the rear. With the locked 50/50 split, the rear end will rotate quite easily under heavy enough throttle, at least with 350WHP. I can't imagine wanting more torque to the rear.

I also wonder how dyno readings would be affected by adjusting the bias.

The biggest issue I have with the '03 & '04 is the lack of front LSD. Torque steer is an issue, especially in the wet. That will hopefully be cured early next year with the arrival of my Quaife.

[krucial]

So whats the big deal with this ACD. Is there any performance benefit from more torque to the front wheels in normal track conditions?

[thatsMR2u]

well if ur gonna race your car ur not gonna blow transfer cases, and if the car has 200 miles on it u can be sure mitsu bone head dealers beat it down, but read some posts thats how alot of people actually swear is the right way to break in a car, I'm not one of those people but it makes some intresting points!

and whattt quaife is going to produce diffs for our cars, thats gonna make alot of owners happy, lets see if they offer there famous lifetime warranty with it tho!

[Crufty Dusty]

Development of Center-Differential Control System for High-Performance
Four-Wheel-Drive Vehicles [1.4 MB PDF]

Development of Super AYC [171 KB PDF]

Research on Aerodynamic Drag Reduction by Vortex Generators [382 KB PDF]

Weight Reduction Technology for Improved Handling Performance of LANCER EVOLUTION [377 KB PDF]

[raywong]

Tarmac: 50/50
Snow: 50/50
Gravel: 50/50

The center diff has a fixed ratio gearing, which is 50/50.
The ACD mode varies the diff's lock state duration and locking power only. In the entrance of a turn, the diff change from open to lock to provide lateral stability. In the middle of the turn, the diff opens to induce turnning. In the exit of the turn, ACD locks the diff again to provide maxium exit stability.

Tarmac: the ACD stay lock for short duration
Gravel: the ACD stay lock for medium duration
Snow: the ACD stay lock for long duration, lowest locking power.

[Ty-Evo8]

Is above true...

[oguratevo]

Originally Posted by Ty-Evo8

I don't have an Evo with the tarmac/gravel/snow settings (got an 03'), but I think it goes as follows:
Snow setting: front wheels get more power/torque (acts more like FWD)
Gravel setting: 50/50 front-back split, power sent equally (AWD)
Tarmac setting: rear wheels get more power/torque (acts more like RWD)

At least this is what I have heard. The setting basically change the % distribution of power from front to back wheels depending on the setting chosen. This change maximizes drivablity/performance in those set conditions (snow, gravel & tarmac).

I agree to this post.

[evo 8 ya]

here is a link that explains how it works. But it doesn't tell the %s

http://www.myevo.com/E7_01.htm

[krucial]

probably because there is no variation in the %s and that guy talking about duration of locking is correct

[raywong]

I do know what I am talking about.

ACD/AYC are controled by the ACD ECU based on the ACD mode switch position, longtitude g-sensor, lateral g-sensor, brake light switch position, hand brake light switch, steering position sensor, and wheel speed sonsors.
ACD can't chage gearing ratio, it only change the open/lock state.
AYC can distribute power between each rear wheel up to 40:60.
SAYC is even better at 30:70.

Raymond Wong
Hong Kong

[HoLeeRay]

Originally Posted by raywong

Raymond Wong
Hong Kong

that rhymes.. and i thought i was only asian person in the world with the name Ray, haha.

as far as the effectiveness of the ACD, i was driving around in the cold rain the other day and i can really feel it pulling me out of corners. i haven't gotten used to it because it takes a moment for it to do its thing and it makes me feel a bit uneasy, but i'm sure i'll get used to it.

[raywong]

If you listen carefully, you will hear the AYC pump activates when you take a hard turn.