My friend who I help do bolt-ons has a GTO M6, he has headers, high flow cats, and catback with cold air (tune is on its way from Alvin). We squared up this morning after work and the TBSS launched him 1/2 car out of the hole and kept it for a couple of blocks...I was very pleased with the power. The best part, half the people I work with were behind us and got to see it. Needless to say, I got some peoples attention. We were all on the way for a beer so there was some shit talking for sure.