I had my K14 rebuilt, it was in bad shape, serious carbon build up in the bearing areas. Anyway, it responds much better and now I can actually hear the whine. It cost me to have it done but I feel better, As for boost the most I can get out of it now is 10psi, I tried to adjust it but must not have turned the adjustment screw enough because it didn't change any. It does spool up quick that is for sure. I pretty much have a new system, rebuilt engine, pump by Giles, and turbo. Hopefully it will last me a long time.