99.5 A4 1.8TQM

I've heard stock boost is 8-9psi. When I fully boost, I get around 12-13. No leaks, I have proper suction also. Im trying to figure out why I can hold this pressure, becasue I'm pretty sure the car wasn't chipped. What else could it be?

Thanks!

 

If you bought the car used the person you bought it from could have put a different N75 valve in the car which would bump the boost a few psi. It could also just have a .8 bar Neuspeed chip in the car, that is 11-12psi.