I don't know what you guys are doing wrong,but I have an '08 SRT.It has a much higher rear than '09 and I can still get 13.1 @ 108 out of it.That was 4 days old with just a K&N CAI and stock tires.I was launching at 2500 and mash on it from go,tried also launching same RPM but not hit the floor till 60' and it didnt make a difference.