sprbxr

I've just completed some track days in my 2006 997 Cup. It's an amazing car with incredible grip. Better than anything I have ever driven.

Anyway, I have a few questions/concerns specifically about downshifting. The gearbox in the car was a brand new (not rebuilt) 2012 version with the latest greatest updates at that time. It has about 15 hours on it now. Every now and then when I downshift from 4th to 3rd it seems to hang between gears. at that moment, if I give shift lever a slight push it will go into gear. It only seems to happen at one specific corner at VIR: turn 11 (I haven't driven the car anywhere else yet)although it did occur at turn 3 twice. I cannot figure out if it is user error or if there is an issue with the gearbox.

What is the recommended technique for a proper downshift? Curious of others experiences. Yes, I am using the clutch on downshifts.


Thanks for the advice.

991cup

Sounds like your not hitting the leaver hard enough ..be firmer

smf32s

Might be the potentiometer on the side of the trans is not set to the proper setting.

Stu

mobonic

My guess would be either one of the 2 posts above.....if not then have gearbox checked...or at least drained and checked for metal pieces.

Have fun with the new toy!

sprbxr

What are the specs in setting up the potentiometer?

sprbxr

I changed the lube when I got it and after 3 hours on the track. Looks perfect.

analogmike

That is VERY dangerous, just doing that ONCE (stuck between gears) can grenade the tranny.

MAKE SURE you always PUSH HARD AND FAST on the shift lever as 991cup said. Also do measure the voltage on the pot to make sure it's in spec.

Viperbob1

Do you have a Motec cable?

sprbxr

I do not have the cable.

I would like to get one.

Viperbob1

The cable allows you to adjust the potentiometer voltage. The range is like plus or minus a couple hundredths of a volt so VERY narrow range.

sprbxr

Now I'm beginning to wonder if the part-throttle jerkiness is related to my shifting issue.

Having never driven a 997 Cup I'm not sure what to expect.

kgorman

viperbob,

MoTeC or Modus cable?

sprbxr

Need both.

coryf

The potentiometer shouldn't affect downshifts at all. Getting stuck in between gears in a "false" neutral is definitely not good. You don't have to be quick on the lever for downshifts. Slapping or tapping the lever can cause the problem. Firm and deliberate downshifts are the goal. You don't have to rip the shifter out of the car. Just a nice solid shift. Do you have a blipper in the car? Make sure you are getting the clutch in just before you make the shift. I cringe every time I see video of guys slapping or punching the shifter when down shifting.

sprbxr

I do have the auto blipper.