You can't double clutch but blipping after shifting is totally useless (like using a comdom after sex) and blipping at the same time (as with auto blipper) DOES work, but not perfectly (like using a condom only just before ejaculation).

 

Right. In case my post wasn't clear, you can't double clutch because the sequential has no neutral between gears.

 

I believe there is something going on in the Motec screenshot that you have not identified. A few hundred rpm of mis-timed shifts will not likely cause the decrease in braking force that you are seeing (nearly 0.9g). I've seen much worse shifting cause only a few tenths of a -g decrease. Momentum of the crankshaft assembly is not that significant; the only thing I've seen cause that kind of change in deceleration is applying throttle. It is difficult to tell from the screenshot how well the dips in Long G synchronize with the blips, but it seems like your clutch is not disengaging (though your clutch pressure is adequate) and the blips are driving the car. Does the clutch fully disengage when hot?

 

okay, so i will show my ignorance. Having never driven a 997 cup with sequential is it typical to use the clutch on down shift? I was thinking that it was not used in most cases? Just a blip as the shift lever was engaged allowing left foot breaking?

 

There are many misconceptions about sequential shifting, but the vast majority of users will use the clutch on downshifts, as it is less likely to make a mistake, and these transmissions are very expensive to repair when abused.

Here is a pedal cam video that demonstrates proper shifting.

 

Why does he lightly touch the brake with left foot when accelerating on a straight? It almost looks like a brake check???

 

Just making sure they are there prior to each brake zone.

 

Hmm, I still had the motec data loaded on my other computer and took a closer took at the blip/clutch release. The blip begins at the same time I start to put the clutch in. The blip is completely finished (0% throttle Pos) when the clutch pressure reaches it's peak. Once the clutch pressure starts to come off from releasing the pedal the long G starts to go back to 0.

I've never noticed any problems with the clutch disengaging when hot... I have a few braking zones (even on that same lap) where I get a downshift or 2 done with no increase in long G so I figured it was operator error and not an issue with the car...


Zulu, I don't want to speak for that driver, but I sometimes do that when I'm having pad knockback issues (pushes the pads back into position for the next braking zone). Typically happens for me coming into T10 at Infineon, mostly when the brake pads are thin and ready for replacement. :-)

-mike

edit: here's a zoomed in motec screen shot of those downshifts with the blue line moved to where things go pear shaped.

 

According to your analogy, I tried to put on condom after my kid got accepted to Stanford

 

yeah, definitely too late...

 

Mike get a auto blipper they are cheap and cheaper insurance...

 

IMO, heel-toe is way easier in a cup. So if he could do it in his RS, he should be able to do it in his Cup; no problem.

 

I WOULDN'T KNOW.. I HAVE NOT HAD A GO IN A CUP.... YET!

 

Yeah, I can heel toe. Just trying to figure out the timing

 

I can heel toe with no problem and saved my tranny with many hours on it. I had the blipper installed recently and just tried it this weekend. IT IS MUCH FASTER ON THE DOWNSHIFTS AND EASY TO BRAKE AT THE LIMIT, WHY NOT HAVE IT ? For me it is really a no brainer...