WharfRat, I also have a '11 GT. I put the Boss Manifold on last night and got it dyno'd today. I also have a tune from BBR.
Did you make any dyno pulls above 7000? On my pulls the tune went pretty rich around 7200 - 7300 and the power dropped noticeably. Posted on the LRS forums asking if this was normal.
![](http://img856.imageshack.us/img856/9353/bossdynorun.png)