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Discussion Starter #1
So how does the rally hand brake differ from the stock hand brake aside from the obviosly missing lock button. How does Subaru avoid total driveline lock up when applying the hand brake either to initiate a drift or further the drift angle before using the power to continue the drift? Because sometimes just bliping the hand brake is not enough to get things off balance.
 

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For Group N it depends on the entry but generally the hand brake is fly off, it may or may not be hydraulic, and it may not avoid total driveline lock up.

For Group A the hand brake is fly off and hydraulic, and the diffs are electronically controlled so there are no conflicts with the hand brake.
 

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SD_GR, I've seen several rally-prepped STIs with "turning brakes". They were all hydraulic, and some of them added an extra caliper onto the back disc, in addition to the standard caliper. Am I correct in assuming a turning brake would have much less of a driveline impact than a full lock hand brake?

Specifically, I saw this on Exedy's rally STI, and on a few others. No idea what class they were in, though.

We used a turning brake on the small dune buggy we built in college. It could almost turn completely around the inside wheel with it, but that was RWD, I'm not sure how an AWD car would respond with one wheel locked.
 

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This was a rally-prepped car. They voided the warranty long before they changed the hand brake. I'm not talking about a street car by any means.

On the rear LSD cars, I could see issues, but with an open rear diff, wouldn't the torque sent toward the rear just go to the unlocked wheel, or would the center diff just get discombobulated and commit suicide?

I don't know for sure the car was still AWD, may have been converted, but I doubt it.

Also, I do remember it was prepped for dirt and gravel, no tarmac.

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SD_GR, I've seen several rally-prepped STIs with "turning brakes". They were all hydraulic, and some of them added an extra caliper onto the back disc, in addition to the standard caliper. Am I correct in assuming a turning brake would have much less of a driveline impact than a full lock hand brake?
I would imagine.

Ford did this with the Escorts that were FWD. The 4x4 Escorts used the same overall solutions that the Subarus used though.
 

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Discussion Starter #9
Ok so the verdict is that my stock wrx wagon hand brake is useless except to park the car lol, so when im out on the snow covered roads and its not drifting but fwd snowplowing(understeer) I should not use the hand brake as a helper as my pumpkin and center diff may puke all over the road. Looks like ill be making my own turning brake set up.
 

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"Drifting" in the snow is not exactly advised anyways. You have to worry more about your center diff, being a viscous coupling, being damaged by excessive power transfers. Heat is your enemy, and a LOT of heat is generated when you're forcing the diff to play catch up at high speeds all the time (during snow drifts). Driving normal on the roads is one thing, abusing it in the snow is another. Your rear diff is put under stress when you're locking up the rear wheels with the e-brake, and your power steering pump is put under immense amounts of stress as well.

We have far too many people who report damage being done by doing stupid things in the snow. Your car was not made to drift, be raced or otherwise abused. So, remember when you do break something, you're responsible and you must pay to play.
 
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