Improve Balky 2-3 Shift in High G Corners?
11-09-2009, 12:15 PM
#31
Rennlist Member
The problem is to perfectly time the syncro ring bringing the next gear up to speed. If you shift too fast (hard) the syncro doesn't have time to accelerate the next gear enough and you get that "snick" that you can quite clearly feel. Friction modifiers like the GM guck or using Redline or similar NS (non-slip) gear oils reduce the slippage giving the syncro better grip which enables it to bring the next gear up to speed faster.
I have always found that you can move your hand very quickly in all aspects of the shift EXCEPT for the split second when you're pushing into the next gear. That part of the shift requires just the right amount of force...too fast and the gear can grind...too slow and it's...slow.
This section of the shift probably represents 10% of the total gear lever movement and is the part that requires just the right touch. The other 90% of the gear lever movement can be done at lightspeed with no issues.
I've always felt that those that have acquired the right touch for this section of the shift are the ones that have their gearboxes last forever. Stirling Moss used to say "treat the gear shift **** like it's an egg".
I have always found that you can move your hand very quickly in all aspects of the shift EXCEPT for the split second when you're pushing into the next gear. That part of the shift requires just the right amount of force...too fast and the gear can grind...too slow and it's...slow.
This section of the shift probably represents 10% of the total gear lever movement and is the part that requires just the right touch. The other 90% of the gear lever movement can be done at lightspeed with no issues.
I've always felt that those that have acquired the right touch for this section of the shift are the ones that have their gearboxes last forever. Stirling Moss used to say "treat the gear shift **** like it's an egg".
07-13-2012, 04:53 PM
#32
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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
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
07-13-2012, 04:57 PM
#33
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most of these replies are wrong, there is clearly a problem with 2nd to 3rd and the only technique which works is exagerated rev matching on the upshift, which we really should not have to do Stirling Moss would not have liked this tranny
07-17-2012, 04:11 PM
#35
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Changed to cup cables and cup shifter, a little improvment. Changed to semi-solid motor mounts - no difference. Changed to new transmission mount - no difference. Went to Mobil Delvac 75W-90 - no difference. Went to fresh Porsche Transmision fluid - no difference. Took a breath between shift - fixed.
07-19-2012, 10:48 AM
#38
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I had the same issues in some corners and if you are positive with the shift and don;t try to rush it, it works. I see students in 6GT3's mess it up often though. When I first got mine I did as well. Coming from my Cayman S, which i could shift more quickly, I had to adjust.
