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Improve Balky 2-3 Shift in High G Corners?

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Old 07-09-2009, 06:14 PM
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redcar1
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Question Improve Balky 2-3 Shift in High G Corners?

Any ideas how to improve the 'balky' 2-3 shift in high G corners?
I have 997 shifter and Cup cables, which feel nice and 'gunbolty' travelling in a straight line, but in a fast turn it is very difficult to cleanly engage 3rd gear.

Is the engine/tranny moving slightly under cornering forces? Are more solid mounts advisable for a car that sees some street use?

Thanks for any advice,

Mark
Old 07-09-2009, 06:15 PM
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cfjan
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Do you have a pic of that Cup cables? Just want to see how it different from the EVO shift link...
Old 07-09-2009, 06:48 PM
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LVDell
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Why would you be shifting in high G load corners? Have you considered short shifting prior to entering the corner?
Old 07-09-2009, 06:57 PM
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redcar1
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Originally Posted by LVDell
Why would you be shifting in high G load corners? Have you considered short shifting prior to entering the corner?
They're fairly long duration corners that are too slow at apex to use 3rd. Not the best place to shift, but there's really no way around it.
Old 07-09-2009, 07:15 PM
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Yargk
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From other posts I've read that:

a.) Solid mounts are a no-no for cars that see the street (unbearable).

b.) Wevo makes semi-solid mounts that may solve the problem and be ok on the street.
Old 07-09-2009, 07:26 PM
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lightguy
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Originally Posted by LVDell
Why would you be shifting in high G load corners? Have you considered short shifting prior to entering the corner?
Bingo.
These cars have plenty of torque to carry through a corner.
Shifting is only going to upset the ballance. If putting the the clutch in (while shifting) does not throw the car, you're not going fast enough.

Yet once again;
Old 07-09-2009, 07:56 PM
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LVDell
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Mounts aren't going to help. As you know, my car was setup as bought as perfect as it could be and the ONLY thing we never did to the car was mounts. Doesn't need them. Trust me on this. I have a very experienced engineer working on my car and has plenty of data to support that conclusion. The deflection from the mounts is miniscule compared to all the other suspension bits on the car.

As far as the long duration corner I'm not sure I agree. I'd need more info. But unless it's the T8 complex at the Turkey F1 track, then I can't imagine what you would be referring to.
Old 07-09-2009, 09:37 PM
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mooty
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i am with dell.
the mount will make car feel different, it may have a more direct feel. but it wont help shifting.
i used to have problem with 2-3 shift. then two GT3 drivers, both 3 seconds faster than me with eyes blind folded showed me how they are faster than me every corner without prob shifting.

the faster of those two told me this "the faster you shift, the slower your lap time will be. slow down the shift, you will drop a seconds off your lap time." now he's only 2 seconds faster than me ;-)
Old 07-09-2009, 11:07 PM
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roberga
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I must be doing something wrong. I have always been instructed to not do shifting in corners for two reasons: 1: to keep the car balanced 2: faster keeping the car in the higher RPM range to track out.
Old 07-09-2009, 11:20 PM
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enthusiast
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Agree with the others the proper gear selection prior to the corner will last all the way through 'track out' without shifting
Old 07-09-2009, 11:47 PM
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va122
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I hAve the mounts and cables and cup shifter and nothing helps
Old 07-10-2009, 12:20 AM
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mooty
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^ slow the shifts.
pull from 2nd to neutral, turn the radio on, find your fav station, turn it off, turn the AC on, adjust air volume, turn it off. than you are ready to hit 3rd.
Old 07-10-2009, 12:21 AM
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Originally Posted by roberga
I must be doing something wrong. I have always been instructed to not do shifting in corners for two reasons: 1: to keep the car balanced 2: faster keeping the car in the higher RPM range to track out.
nah....
i shift before entering the turns.

when i am bored and wanting to scare myself a bit, i would do a mid turn shift.
Old 07-10-2009, 02:31 AM
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DRG13
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redcar1 races Ferrari's, he's no novice guys
Old 07-10-2009, 07:40 AM
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lightguy
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Originally Posted by DRG13
redcar1 races Ferrari's, he's no novice guys
If the linkage/mounts/shifter is as solid as one can get;
try GM Friction Modified oil in the tranny.
75 to 100 %. It smooths out shifting in cars with notorious 2nd gear notchiness like the NSX.


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