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see if u were to read... it says:

The DCCD is a just a special type of limited slip differential (LSD), so to understand how it works, one needs to first understand how basic differentials work, and then move on to what the "limited slip" part does, and then finally examine the special feature of the DCCD, the fact that the amount of "slip" in the "limited slip" portion can be adjusted, either by onboard computer or by the driver.
 

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Ok...enough about the DCCD lol. That vid was pretty cool. I remember reading about it in SCC. O btw, "bonecracker," in the future could you consolidate your numerous posts into one or two...it makes reading the topics easier. Thanks :tup:
 

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Discussion Starter #24
wow. landslide!
 

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Everyone is always talking about power being transfered from front and back.

But you forget about Left and Right!

When the DCCD is in the LOCK position it LOCKS 50% to the LEFT F&R and 50% to the RIGHT F&R. THAT'S is why you get binding/jumping in a turn because the L&R axes are locked. (hence ones guys mention of 4WD which is correct)

Now changing the DCCD to auto or open and the DCCD will vary the drive torque distribution from 35:65 (04-05)/ 41:59 for 06+ to 50:50 (lock). Thats why in a tight turn you don't get binding because the LSD clutch allows the L&R/F&B wheels to turn at differnet speeds.

In Auto, the computer will vary the Torque (NOT POWER) distribution based on the following sensors imputs from:

ABS Actuation Imput Control
Brake Switch Imput Control
Park Break Input Control
Tight Cornering Control
Slip Control
Cornering Control
Control based on Lateral G Sensor Signal
Accelorator Posiotion Sensor
Control based on Wheel Speed Sensor
DCCD Dial (Manual Control)
Fail - Safe Control (if computer senses any problems it will put the dif in full open)
Rear Dif OIL Temp Sensor (if dif oil gets too hot>150' then it will reduce LSD clutch engagement until temp comes down)

Remember the Power/Torque to the center Axle is fixed. The drive shaft can't change the amount of power the engine is puting out. It is what it is...

Its the LSD clutches (differencials) that takes the power/torque from the engine and controls it to the wheels based on all the sensors listed above... It is this (differencials) that changes the amount of TORQUE the wheels get.

All info has been taken from the 2004 Subaru Tech Service Manual so I ain't making this $hit up!

But trust me, I think you had to be the one who invented the DCCD to really understand it!!!!!

I encurage EVERYONE to donate to this wonderful website/forum and you will be able to read up on the DCCD in the donating members only section!

DO IT so we don't have to keep trying to clear up all the misconceptions about the DCCD and what it ACTUALY does!

Jay
 

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Let me see if I heard you right... Did I hear that in the event of the Emergency brake being pulled the rear wheels will (for all intents and purposes) freewheel and allow the engine to keep running even though they are locked up? Is it possible to do a handbrake spin while the car is in gear and the clutch out? I have little experience with truly aggressive driving but I have had many fun times doing handbrake turns. I have always done them with the clutch in or the car in neutral as I thought that in a rear wheel or AWD car it would cause the engine to stall. Does it? I have never wanted to try it without pressing the clutch, but to have power to take you throught the turn would be a great way to get the car into a drift. Is this how drifts are started?

Sorry to go so far OT but I just got a flash from that cool bit of info on the DCCD. Thanks for that BTW.
 

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STI_Mike said:
that car sounds awesome!
I only imagine what it sounds like inside the car!


wait...I know ;)
 

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jaydow11 said:
Everyone is always talking about power being transfered from front and back.

But you forget about Left and Right!

When the DCCD is in the LOCK position it LOCKS 50% to the LEFT F&R and 50% to the RIGHT F&R. THAT'S is why you get binding/jumping in a turn because the L&R axes are locked. (hence ones guys mention of 4WD which is correct)

Now changing the DCCD to auto or open and the DCCD will vary the drive torque distribution from 35:65 (04-05)/ 41:59 for 06+ to 50:50 (lock). Thats why in a tight turn you don't get binding because the LSD clutch allows the L&R/F&B wheels to turn at differnet speeds.
Much misinformation here.

The dccd has nothing to do with the torque distribution between left and right. Thats what the front and rear diffs do. The binding is because of the difference in rotation between front and back drive shafts. There is no way to lock the axles on an sti, just the center differential.
 

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Nice burnout!
 

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elirentz said:
Much misinformation here.

The dccd has nothing to do with the torque distribution between left and right. Thats what the front and rear diffs do. The binding is because of the difference in rotation between front and back drive shafts. There is no way to lock the axles on an sti, just the center differential.
Right. DCCD = Driver Controlled Center Differential. The center differential controls power flow to the front and rear driveshafts. Those driveshafts then connect to another pair of LSDs, one front and one rear. Those front and rear LSDs control power flow to the left and right wheels on their respective axles only. There is nothing in the STi AWD system tieing the left front and left rear wheels together, or the right front and rear wheels.
 
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