If you have no leaks, the jetting, timing is spot and you have on you should feel some sort of distinct power band. I would keep messing with the jetting, then once you feel like it’s doing what it’s supposed to get the files out and get to work. The kstar is a super candidate for porting.
The reason why your buddies is faster in nut shell; the airsal, having higher blow down and the exhaust is timed more aggressively. It comes on hard but is more peaky, where as your kstar has 6 degrees less blowdown, and ~10 degrees less exhaust duration it will have a more broad and has a less pronounced power band. Both of you could widen and polish the exhaust, if you raise the exhaust duration you should be faster as you will have better scavenging due to the boost ports.