Some updates:
It was a lot of work trying to get to the track on Saturday, but I've managed to install everything, but there are some faults that should be corrected.
First we have installed the front brakes and a rudimentary cooling duct:
Because I couldn't be there i asked the mechanic to try to connect the duct in the center of the disc where the vanes take air, but he connected them to the side of the disc.
He also told me that the calipers were perfect centered and he didn't even have to use the spacers from AP Racing. I found out later that it wasn't so.
Then we have installed the S3 rear brakes:
This was the final result:
After this we've tried to do a quick geometry because it was 11 at night and I had to be ready for the track the next day.
After only 30 laps of a 3,3 km circuit the front right tyre, a new DMACK Trackday medium tyre looked like this:
Unfortunately, the ducts were pulled off from the brake shields and the cooling didn't work, the heat shields stopped the vanes to take colder air.
Also the pads were new, and the calipers were not correctly centered so the exterior pads were always in contact with the discs. This has caused a lot of heat, I boiled the new Castrol RBF brake fluid and my top speed was about ~10Km/h less than the last time. I was also slower then the last time by 1.5-2 seconds per lap.
This is how the front calipers look now, on the exterior they are purple:
The slower speeds can have 2 causes: it was hotter by 10 degrees C and my timing was higher than usual (revo settings 6) or the brake pads were always in contact with the discs and this was slowing me down.