Ive had a few Imprezas in the past including a Version 4 Type R so I'm aquainted with the handlling of these cars with and without a dccd, however, I now have a 05 STI UK with DCCD-A and I've noticed a strange feel through bends. Even when going slowly in a high gear (about 1300 rpm), the slightest throttle coming out of a roundabout / corner will make the car feel like bad understeer requireing upto about 1/8th of a turn extra lock to retain the chosen line. Conversly, lifting off will have the opposite effect. It feels like the front is tucking in/ running wide. The geometry (more aggressive than OE but not as much as the prodrive settings) has been set, and checked by a different company so I think thats ok. At higher speeds, this is even more pronounced. Changing from auto to open and winding the diff forward doesnt seem to affect it very much. This is the only DCCD-A car I've driven. Is this behavior normal for an 05? Is it a symptom of the type of front diff these have?

My JDM 03 STI (DCCD-A) does the same thing as you mention above. You have done well to explain it. I cant really remmember what my UK STI (again 03) plate was like as that was over a year ago. I dont think it did it though.

I have exactly the same with my 05 STI , I find it can be at it's worst when accelerating down a slip road with a slight bend on it , as you lift off to change gear the car likes to tuck in which certainly wakes you up a bit :confused:

Dave

A very in depth explaination of DCCD here DCCD Explained - ClubWRX Forum - Subaru Impreza WRX and STi Community and Forums (http://www.clubwrx.net/forums/sti-transmission-drivetrain/72222-dccd-explained.html)

I have exactly the same with my 05 STI , I find it can be at it's worst when accelerating down a slip road with a slight bend on it , as you lift off to change gear the car likes to tuck in which certainly wakes you up a bit :confused:

Dave

A very in depth explaination of DCCD here DCCD Explained - ClubWRX Forum - Subaru Impreza WRX and STi Community and Forums (http://www.clubwrx.net/forums/sti-transmission-drivetrain/72222-dccd-explained.html)

3 of us now have the same problem (is it a problem).. is it supposed to do this..??

Its actually very frightening if you are accelerating hard and as you say lift off to change gear.

The 05 wrx I had before certainly didn't do it. The thing that makes me wonder, is that switching the diff from auto to full open, doesn't change the behaviour at all. I wonder if its a peculiarity of the wide track STIs?

3 of us now have the same problem (is it a problem).. is it supposed to do this..??

Its actually very frightening if you are accelerating hard and as you say lift off to change gear.

When I got my STI last year I looked into this a bit because I thought something was wrong with my car , a few people on here replied to threads saying they had similar things .... http://bbs.scoobynet.com/scoobynet-general-1/647223-05-sti-dccd-handling-question.html
I did find an article in CAR magazine (June2004) which was a test drive of the WR1 when it came out , this had the DCCD in the 05 STI's and part of the article read....

"if you lift mid-corner you get a big, floating body movement and a tendancy towards oversteer. Better to hit the four-pot Bembos early and then throttle harder earlier in the process"

After reading this I just figured they must all be the same and I was just being a bit fussy:confused:

I hope this helps you guys , but if you find out anything further I'd be very interested to know :thumb:

Dave

Yep, it definitely takes some getting used to.
Best bet is to brake before the corner and get on the power early. Never lift off suddenly mid corner in a A-DCCD scoob at speed, or you'll probably end up in the bushes ... IMO, this is the hardest thing to get into your brain, as it goes against what your instinct and experience of driving other cars are telling you to do.
Lots of practice in a big open space and you should start to get the feel for it.

"if you lift mid-corner you get a big, floating body movement and a tendancy towards oversteer. Better to hit the four-pot Bembos early and then throttle harder earlier in the process"

Brilliant, this is EXACTLY what I get and wondered what the hell was going on.... First time it happened I was going through the Dartford Tunnel and as I lifted off it went all floaty on me with the back feeling really light - absolutely cacked myself :eek:

Now I know that it's all part of the process and nothing to worry about :notworthy put my mind at rest I can tell you

I have a 2003 Spec C and it feels really floaty but only when pushing on hard through corners. I dont tend to get the understeer at all though? Just really really oversteery. Seems like fun to drive but its not the quickest line on track!

Never had anything bad on road speed though....apart from when the tracking was wrong and the thrust angle was making the car behave quite eratically.

yeah, definitely no understeer which is why I didn't reply to the op. But when someone mentioned the floaty feeling iwhen you lift off mid corner it reminded me.

Brilliant, this is EXACTLY what I get and wondered what the hell was going on.... First time it happened I was going through the Dartford Tunnel and as I lifted off it went all floaty on me with the back feeling really light - absolutely cacked myself :eek:

Now I know that it's all part of the process and nothing to worry about :notworthy put my mind at rest I can tell you


:thumb:

It does take some getting use to, what you need to do is let the A-DCCD do its job, the thing is that it will correct itself, you get the feeling it is oversteering when going into a left hander for instance and your first reaction is to correct it, just let the car do it for you as it will correct itself :)
Weird feeling but it just takes some practice to get use to it :)

Tony:)

It does take some getting use to, what you need to do is let the A-DCCD do its job, the thing is that it will correct itself, you get the feeling it is oversteering when going into a left hander for instance and your first reaction is to correct it, just let the car do it for you as it will correct itself :)Weird feeling but it just takes some practice to get use to it :)

Tony:)

Spot on.

I find it improves with diff almost full open (2nd from back).

Also in Hawkeye they changed Diff settings to send slightly less power split to rear which reduces understeer a little & I would imagine a little easier to drive in above instances.

Just out of interest have you tried with diff more in locked positions to see what happens?

I have exactly the same with my 05 STI , I find it can be at it's worst when accelerating down a slip road with a slight bend on it , as you lift off to change gear the car likes to tuck in which certainly wakes you up a bit :confused:

Yep, I get the same feeling too :lol1:

I`ve messed about with the settings but I can`t tell the difference, well not on the road anyway.



Neil.

Only time I've had it is mid-overtake, on a slight bend, rear end snapped out when I changed gear 5-6k, then immediatly came back again..:freak3:

Papped me pants....

Now I'm much more gentle with the throttle on anything other than dead straight!

Another good article explaining the DCCD here Subaru Drive Performance Magazine : DCCD - Driver Controlled Center Differential (http://www.driveperformance.subaru.com/version1_2/blueprint.asp)

How well does a stiffer rear anti roll bar do in countering the initial understeer tendency?

I dont know how the GC8 handling crosses over the the later car but I find that one click from full rear give the best balance in our STi6 :)

I find that the more rear bias you have the less the car understeers but you get to a point where you want a little more drive to the front hence one click from rear rather than full rear.

Another good article explaining the DCCD here Subaru Drive Performance Magazine : DCCD - Driver Controlled Center Differential (http://www.driveperformance.subaru.com/version1_2/blueprint.asp)


Another BAD article as its totally WRONG.

The DCCD does not 'adjust' the torque split, that is fixed by the mechanical function of the epicyclic centre diff, the DCCD adjusts the 'locking' (actually the amount of limited slip), which (when slip occurs) may adjust the front rear torque split, but in no way is this torque split controlled by the DCCD! as you can tell by reading the forum thread linked to by in the sticks (A very in depth explaination of DCCD here DCCD Explained - ClubWRX Forum - Subaru Impreza WRX and STi Community and Forums) as that gives a different explantion (they couldn't both be right, could they!)

I wish I could get paid for writing a load of tosh!


I find that the more rear bias you have the less the car understeers but you get to a point where you want a little more drive to the front hence one click from rear rather than full rear.

What you mean is a little more locking so as the rear starts to slip torque is transferred to the front (its still rear biased) of course!

Simon