The FP STAR kits allow the transmission to shift quicker than stock - reducing missed shifts and the damage cause by missed shifts.
With stock shift mechanism parts, normal optimal Dynojet QS shift kill time in upper gears is around 50ms to 55ms.
The STAR kit shifts quicker, so, 40ms to 45ms is normally more correct.
I'd guess that if one were to also blueprint and reshim the gearbox gears, you might be able to make it shift another 5-7 ms quicker
Having too much kill time for the shift mechanism causes clunky shifting.
To do a preliminary Kill time setup on an EC997 dyno, set
dyno RPM to hold 3/4 of redline in top gear (if it's a 10k redline, set hold at
7.5k), then downshift to 2nd or 3rd and let rpm drop down to idle. Open throttle
fully and shift at redline in each gear, until you get to where the dyno is
actually holding 4th or 5th at some rpm before redline (it will be a higher rpm
than 7.5k in our 10k example),
You should be able to upshift at full throttle in 4th, 5th, 6th. Shoot for the smoothest shift transitions. The lightweight EC997 dyno roller reacts very quickly to power changes.
What I've noticed is that shifting by hand gives better feel than shifting with your foot and that it's quicker to have two people - one to make the kill time changes and one to work the throttle and shift.