Adjusting TT6 CompetitionClutch Twin Discs Clutch

Hi everyone,

just a little question, I 've changed the clutch of a friend's TT6 for a brand new CompetitionClutch Twin Discs kit (with new flywheel and a new hydraulic central bearing)

Everything went as planned excepted from the adjustment of it.

Is it possible that the OEM clutch cylinder at the pedal has to be changed for a an other longer one ? Or at least, is it possible the cylinder rod is now not long enough to be able to push de clutch far enough ?

I'm now at the very end of the available adjustement at the pedal, but this still isnt enough. The gearchange is ok when wold, a bit harder when hot.

BUT you don't have to let the pedal up more than 5mm to make the clutch gripping and moving the car.

This means the clutch is just disengaged when the pedal hits the floor, but it should be a bit more disengaged...

Do you guys have some feedback about this kind of "problem" with an aftermarket clutch ?

The central bearing is quite close to the clutch without pushing on it (and without touching the clutch pedal for sure) so no more available adjustment there.

Thanks in advance,

Jérémy

Are you saying you have removed the stock clutch fork and fitted a concentric hydraulic release bearing? If so you will have to match the concentric release piston area to a suitably sized master cylinder. From what you say you need a bigger bore master cylinder. Please clarify just what you have done.

Yes that s it, I fitted a concentric one.

But I think the bore is enough.

I didnt t know I have to adjust that much at the pedal (the oem adjustement is not enough).

I ve to adapt the pedal mechanism, I ll leave here some pics of my mods if everything is ok.

Thanks Chris

The pedal pushrod adjustment can only take out free play, it can't magically give more slave movement per X mm of pedal depression. I think, if I understand what's happening properly from your description, you need a bigger bore master cylinder. (Or a smaller "bore" concentric release. Ideally you want to get to the situation where you need a pedal depression restriction stop on the floor, so you can't over travel the bearing, but you are sure to have enough movement for full release.Or it could be the concentric release needs spacing nearer the clutch from the face of the bellhousing.

Hi Chris, I got some news :

I changed the master cylinder for a 3/4" bore one.

This was not really easy as I couldn't find any with the conenction at the right side (left)...

I had to design a piece to relocate it at the right side to be able to reuse the oem rigid tubing.

I made some fitting test with some 1/1 paper printed templates :

I finally machined the part out of a steal block :

The final product :

Everything works like I should

BUT

My gains are very small, I don't feel a huge difference, this seems to be better, the pedal is harder but I had expected way more gains haha ...

My little test travels don't show any sign of problems (even with the oem 5/8" master cylinder), apparently the shifts were harder on long travels as my friend explained it, I'm curious to see how this will be with this combination...

Oh and the concentric release can't be nearer as it is now...

EDIT : hum how could I display the pics larger and correctly turned ??

Jesus, what was wrong with a length of dash 4 hose.... Very nicely done, but a bit over complicated methinks So does it fix the release issue or not, I am not sure what you are saying about that... Is the release bearing the right face contour and the right diameter for the clutch cover fingers? Flat face bearing or convex? Straight finger cover or curved? What bearing do the clutch people expect you to use? Are you using that one???

Haha I didnt wanted to touch at the stock tubing and this was very close to the turbos (30mm) so... I m not à mechanical designer for nothing x)

The release bearing was included in the clutch kit (I ll do à pic tomorrow).

Didn t take pictures but everything is now working like it should.

I m happy with my little machined part, it works very well !!

Thanks for the help Chris

No worries, that elbow is a work of art!