Handbrake and 4wd..

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Handbrake and 4wd..

Postby RS13 » Thu Nov 13, 2008 5:42 pm

Just a quick question, how much damage does it do to the centre diff using the e-brake to initiate a slide in a 4wd car, say WRX or GT4 etc?
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Postby B1NZ » Thu Nov 13, 2008 7:09 pm

Im not sure on the damage, but I know if your trying to initiate a slide it seems ineffective unless you stab the clutch at the same time.
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Postby RS13 » Fri Nov 14, 2008 11:19 am

B1NZ wrote:Im not sure on the damage, but I know if your trying to initiate a slide it seems ineffective unless you stab the clutch at the same time.


So if you locked up the rears, the centre diff (if a normal open diff) would just transfer all drive to the front wheels? But a viscous centre diff would be forced to spin against the clutches, and therefore burn out quickly?
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Postby edwagon » Fri Nov 14, 2008 1:42 pm

A viscous centre diff doesn't have clutches as such, they're more like serated plates which are tightly packed in a thick gel which gums the plates together and makes it hard for them to turn against each other. They do become less effective over time but you won't burn them out doing handbrake slides.

Id be more concerned about the damage you'll do to the drivetrain when you give it the jandle as you power out of the slide.....
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Postby RS13 » Fri Nov 14, 2008 4:42 pm

Sweet cheers. :)
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Postby RedMist » Fri Nov 14, 2008 6:14 pm

B1NZ wrote:Im not sure on the damage, but I know if your trying to initiate a slide it seems ineffective unless you stab the clutch at the same time.

I've seen the same problems on tarmac. It's bloody abusive on drivetrain but the best way to start a slide. It becomes a combination of handbrake while clutch in and poping the clutch that promotes a slide. It's also considerably harder to throttle control the slide... unless you have a tonne of HP or seriously screw with your suspension geometry you'll be pretty much on the peg, which makes it impossible to bring the arse end around further.
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Postby rollaholic » Fri Nov 14, 2008 6:22 pm

if you have the clutch in there is no drive being transmitted to any wheels.

as mentioned its what happens after you get the rear swinging that does the damage :D
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