I've had a V44 plug-in on my RB26DETT since 2008. I recently changed my timing belt and set the CAS back to roughly the same position. The car has been driving fine. The other day I checked the timing and discovered it was 10 degrees over advanced, so I retarded it by 10 degrees after double-checking with a different timing light. Now the car drives worse than before. It hesitates coming on boost and makes much less power. I removed the top timing belt cover and confirmed the cam pulleys were correctly lined up with TDC. I also confirmed the cam half-moon shaped key for the CAS is still in position and hasn't broken off. So I'm at a bit of a loss as to where this 10 degrees of offset may have come from. Does anyone have any ideas? Oh yeah, in setting the timing, I upgraded my firmware. I think I was about 4 or 5 versions behind the current release. Would this have caused any issues? In the base timing adjustment screen, the original offset (for 10 degree ref) was -82, as set by the Vipec tuner. Now it is -96 for the timing to be right. Do either of these numbers sound about right for an RB26? One other thing, I did change the timing belt somewhere around 2008-2009 after the Vipec install and tune. I went back to the workshop and they checked the timing and adjusted the offset from -80 to -82. I was wondering in my head if the timing belt was always off by 1 tooth, but the fact I've changed the belt once already and it made minimal difference to timing, makes me think the possibilities are very slim.