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I was practicing handbrake turns the other day and realize that I may have been screwing up my the diffs on my STi. I know that in normal 4wd cars, you need to depress the clutch before handbraking so you don't screw up the diff by making the front and rear wheels go at different speeds. I also know that applying the handbrake on the STi unlocks the rear diff because of the DCCD system.

So, my question is... can I pull a hand brake turn on the STi without being in neutral? That is can I be in 1st or 2nd gear while making the 180 so that I can start hitting the gas just as the car turns around? I've seen the drivers on the WRC do this. These drivers have the front wheels gripping hard as the make the handbrake hairpins and as the let go of the handbrake, the rear wheels start biting in. Can I do this on my STi or will it be wrecked?

Thanks!
 

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check the handling and braking forum. The STi DCCD automatically disengages when you lift the parking brake just like the WRC unit it emulates (part of the homologation rules of WRC that we benefit from :D )
 

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I'd say you want to practice this on a slicker surface such as snow or wet grass.

When you pull the e-brake up, the DCCD changes to 0% lock on the CENTER diff, not the rear. Note that it then becomes just a diff, not a limited slip diff. Due to the mechanical design, it is still geared to send 65% of the torque to the rear axle. If you pull the e-brake hard enough to stop the rear axle from turning though, this means all the power is sent to the front. Keep in mind there will be a substancial amount of force trying to turn that rear axle from both the ground below the tires, as well as the drive shaft out of the center differential.

I see no reason why it wouldn't work great on a slick surface. I doubt it can be done on dry pavement though, although I don't own a STI. I'd personally love to see somebody prove me wrong on this.

Part of the reason it works so well in WRC is that their hand brake uses the brake fluid to press the calipers, not the mechanical e-brake drum design like the USDM STI has.

-Lance
 

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I have pulled the hand brake on dry tarmac and successfully lit up both front tires with throttle input. The backs went along for the ride and did not spin or push the car.

The car also behaved exactly as the WRC car seems to in their hand brake turns = the rear end whipped out and a pendulum turn is easily achieved, however over rotation is also easy to achieve and you can end up nosed into the apex or backed off the outside of the turn if you are not careful. Careful throttle input can also induce a nice prediuctable AWD drift :D TONS of fun with the right practice and plenty of extra room to prevent contact with stationary objects or other cars.
 

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I did some playing with the handbrake tonight in the snow; I was in 50-50 lock, and when I pulled the brake I did notice something going on with the LSD, but I wasn't sure what. Could have been just releasing it. Anyways got some nice 'Dukes of Hazard' slides...
 

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ValvetrainEngineer said:
I did some playing with the handbrake tonight in the snow; I was in 50-50 lock, and when I pulled the brake I did notice something going on with the LSD, but I wasn't sure what. Could have been just releasing it. Anyways got some nice 'Dukes of Hazard' slides...
any pics?
 

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so your tellin me that i can be in 1st or 2nd gear, and floor it and pull the handbrake and just drag the back tires while im flooring it? the front tires will just pull?
 

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Holy threadbump Batman!
 

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jesus christ.....that must be the mother of all bumps
 

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That's nuts. haha. 5 year old thread FTW! And I wouldn't recomend doing any "flooring it" and locking the steering wheel. Unless you're on a competitive level I just can't justifiy being that harsh on a car. In autoX I can see it being usefull.
 

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i could see yanking the e-brake flipping the wheel and gassing it but i wouldnt hold the wheel at lock....bye bye PS pump....it cant be good for the diffs in the long run either...i bet its fun once or twice tho!
 

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i just noticed.....31 posts since 2003 for the OP!
 

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i must have mis wrote it, i didnt mean to lock the steering wheel, cause yea i know that could or would mess up the PS. i meant like can you be going like 30 pull the handbrake to whip the back end out and then drop it in a lower gear and press the gas to keep it sliding, or do you release the handbrake as soon as you whip the back end out? this is what ive been doing when i pull the e brake. push the clutch in, e brake, let go of e brake, then engage the gear. but it doesn't usually work haha. i need to do this on wet grass or something so i can practice without hurting anything.
 

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I had a problem with center diff locking in tight turning conditions,no not in manual mode,to find after inspecting the speed sensors that there was an excessive amount brake material on the them,(hand brake dust from e-brake turns)thus causing an erouneous signal to the dccd system,or lack of signal.I cannot believe the DEALER couln't find this problem.I agree that it's just plain abuse to ride that treats you so well.I now know the system pretty well thank's to the lack of support from the central american people,TICO"S HA! Thank you
 

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The 04 and 05 STi DCCD's are the only ones that can go completely open when you hit the e-brake. 06+ STI's all have a mechanical LSD for the center in addition to the electronic locking, and its only the electronics that unlock with the e-brake. So there is the potential for damage and/or increased wear on the center diff doing e-brake turns for the 06+ model years.
 

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Thank's for the reply,I wan't to share that the possiblity exists for the metalic brake lining of the E-brake to cause a tight cornering situation of those who choose to abuse their cars,due to accumulation of brake material.I see by your handle(user name) that its possible you are or former owner of a (951);944turbo.I had 87 944t double shim the waste gate chip the cpu and injector mode,open restrickter of timed charge vavle ect.......go.....fast....yaa!:tup:
 

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