Well Lads,
As the heading says i just have a few questions regarding the DCCD.
Have used the search button but still have a few queries regarding it.
Am i right in saying that when the DCCD is fully back the power is 70%Rear and 30%Front??.
Then when it is moved forward 1 more notch it is 50-50??.
If you want to get as much grip off the line which would be the best setting in the dry/wet??
Would appreciate any help anyway,
Thanks,

 

Yes I think that's right. 70/30 fully open. I use it fully open all the time. Then when it's wet I put it up 1 notch. Second green light.

Paul g

 

Is it the same for all models with DCCD?

 

The torque is fixed, all the DCCD does is alter the amount of slip (think of it as a variable limited slip diff.) between the front and rear axles.

It depends on the car as to the torque split, early classic RA's I think were more rear biased. I'm sure someone will be along later to tell you all you need to know, but remember is doesn't alter the torque split between the front and rear wheels!

 

https://www.scoobynet.com/technical-...anslation.html

There is another topic in the tech archive too

Tony

 

Cheers tony.

so on diff free, the ratio is 36/64 front to rear.

When this was said "the setting is infinately variable between 0-100% locked" in the 2002 thread, does it mean that at some point on auto/diff lock you could have 100% of the power to the rear wheels ?

No laughing!

 

On the new age cars equipped from 2003, yes, most of the time is will be to the rear (depending on the percentage as they are different on the classics and newage but never 100%, just the maximum stated f/r percentage), going into corners it will change and move the power more forward giving better grip and levelling back up straight coming out of the corners it should be then adding the power back to the rear
Its a little more interesting if you turn auto off or have the manual only version, you sort of learn how the car handles, though auto is far more accurate

Tony

 

Cheers tony, so would the maximaum stated f/r precentage be the 36/64 f/r above, the minimum being 50/50? Presumably it never has all the power at the front wheels?

 

Always a higher percentage to the rear than the front but it differs between model types/years, ie the blob eye is different to the hawk eye for the split f/r.

Tony

 

Ok as far as I can make out, classics have a 36:64 f/r split (to 50/50), 35/65 on blob new age and 41/59 hawkeye split.

Tony

 

Cheers tony.

Sounds like on the Hawk Sti it varies front to rear 41/59 to 50/50 then.

Andy Tj

 

So its 41 front / 59 rear on the hawkeye with the DCCD all the way back (bottom green on the christmas tree)

So as you move it further to the top of the tree it gets closer to 50/50 and then lock does what?

 

Lock is 50/50

Tony

 

Thx for that Tony

Another question, on that tech link I think it states to have the car in "lock" for ice, gravel, fast road?

Lock for fast road use? I thought the general concensus was have the DCCD all the way back (i.e. the very bottom green one

Plus sometimes when its in auto/not in full green occasionaly theres a real knocking noise when turning at low speeds, is that normal?

Cheers

 

All the way back normally on straight roads, move it up a few notches for corners and the knocking is normal when turning at low speeds as that is the diffs winding up

Tony

 

DCCD changes the amount of lock on the centre diff., it does not change the % power split front to rear. imagine a rear open diff. and then a limilted slip diff. and then a welded diff. such as in a drift car. DCCD is a variable limited slip diff. with you being able to vary the amount of 'slip'.
This is why they knock as Tony say above when turning tight corner such as parking; because the front and rear wheels are trying to turn at different speeds but the centre diff. is trying to make them travel at the same speed because it is 'locked'.
There is a good thread on NASIOC IIRC.

 

Does this mean that the DCCD should be all the way back "green" when parking etc? I know that the knock is said to be normal but I'm an old fashioned guy (or is that just plain old ) and any knocking conjures up images of metal on metal = not good

 

Its just the diffs, hence differential, difference between the wheels, so the diff "adjusts" itself and winds up to compensate, but yes, all the way back on green is better for parking

Tony

 

Excellent.

Thx for all the help

 

I keep my Hawk eye 07 dccd in the last green (open diff) all the time, but every time I switch her on the system defaults to auto, I feel like an airline pilot having to startup then set running gear to rear open diff for every take off lol

 

Lol I do that too. I am guessing it has no effect on drive train parts or fuel economy set in the last green?

 

If your doing some "energetic" driving, leave the car in auto, it will be better than what you can do
Normally on a straight road you wont need to do anything except the last green, coming up to a roundabout for instance, you will have to move the diff forward to nearly lock so that the tail doesnt step out, then out the other side and back again to the last green, by the time i wrote that, your auto dccd would have done over 100 actions thats how good it is

Tony

 

Since i'm buying an Impreza with DCCD soon (classic) my understanding is

Green for normal driving (square or triangle illuminated)
Green for parking (square or triangle illuminated)

Should/can the various stages of Orange be used on the road?

What about weather/road conditions still keep it in the green or use orange?

Would it be advisable to find a nice open space to practice using it (legally)?

 

You can use green in wet weather, move it forward for corners/roundabouts, but mainly mine is green for straight road/town use.

Tony

 

I thank you

 

anyone know where i can get an english manual for my Impreza Type R version 5?

 

I really doubt if there is any.
If so - anyway hard to find I guess. But to be honest I don't find anything really complicated in that car as for a driver

 

Strangely - for me the opposite applies. I find auto works best for town,wet,motorway driving and green allows much harder cornering on the twistys in dry conditions. Plus, in dry weather the car can definitely hold a higher cornering speed as the diff is dialed away from auto and almost all the way to diff free, after which it likes to oversteer.

 

this is the correct discription of what the dccd does,as gpssti4 says it does not alter the power split from front to rear.

 

I drive a Bugeye WRX and it's 50/50 permanent. To be honest i've been driving it for the last 5yrs like that and i have to say it works very well. Mid bend doing 80/90 on a sweeper just turn a bit more and then a tiny bit of opposite lock it gives you all the controlled oversteer you want and feels so in control doing that.

The only thing with 50/50 is on slow speed bends/corners when pushing on a bit out of the corner understeer can be a bit of an issue and that's the time when i wish i could have some rear bias as that would get rid of some of the understeer and make turn it just that little bit better.

Eventually i'll switch to a late 6spd box and will be able to do that but 50/50 feels very solid on the road in just about all conditions.