After a weeks worth of autotuning, seems my boost gauge is damaged. I guess all of the high rpm, low load situations damaged the internal diaphragm or something. Now with engine off it reads 2" vac, and will get up to 28" vac while decelerating as opposed to the 21-22" that it would read previously...

Does anyone know if it is possible to re-calibrate an autometer mechanical boost gauge? Or do I just need to buy a replacement one?