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      07-16-2009, 11:30 AM   #67
lucid
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Quote:
Originally Posted by KINGLEH View Post
i think before this goes any further we should establish what we should call this situation...

the original poster is calling it "lock up" but what i think he means is its trying to lock up.... of course ABS pulsing the tire does actually lock up for a hundredth of a sec or so.. but I personally dont call that lock up...

Noone should actually be able to LOCK UP any of their tires unless they get a ABS fault and the system fails... That still might not be the case because I'm even pretty sure i had ABS fault light on my dash after Dynoing my car and went out and tried to lock up a tire to see if it was totally off and ABS still cycled....
I agree that what we are discussing is not all that clear. We all agree that none of the wheels will lock up due to braking torque. However, one should be able to lock the drive wheels up via the transmission during a downshift with a manual transmission. I suspect it might be possible to do that with DCT as well in some modes, but that is just speculation on my part as I haven't driven it on a track.
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      07-19-2009, 03:17 AM   #68
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what is so confusing about trail braking. brake late in a turn. less wieght is on the rear tires. rear steps out becuase of less traction. doesnt matter if you have ABS, DCT, SMG, or ABC, its about weight transfer.
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      07-19-2009, 10:01 AM   #69
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Quote:
about weight transfer
Agree.
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      07-19-2009, 10:13 AM   #70
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Originally Posted by sayemthree View Post
what is so confusing about trail braking. brake late in a turn. less wieght is on the rear tires. rear steps out becuase of less traction. doesnt matter if you have ABS, DCT, SMG, or ABC, its about weight transfer.
Nothing confusing about trail braking. What the OP is describing does not seem to be clear when he says his rears "lock up"--at least to me. That's why ABS and DCT came up.
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      07-20-2009, 10:41 AM   #71
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I did my first track event at TGPR last week, and the brake bias felt perfect. The track has a couple of corners with banking at entry and another one with a decreasing radius. The car was able to go in deep on the brakes and rotated perfectly.

As Leh described... I did feel the occasional rear ABS kick in, and I think it was usually after the front brakes had become too hot (I was on stock pads).

Even with the DCT rev matching I still had to be aware of the additional engine braking that came with downshifting. Without coming off of the brake slightly or decreasing steering input, the car would want to step out at times right when it downshifted. Maybe this is what the OP is talking about. It just takes a little compensation to keep the downshifts from upsetting car too much.
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