You're running FI though? 30k miles is not a lot for a clutch on a stock car, but obviously if you're making more HP than stock, and more importantly more torque, the clutch can and will burn out faster, depending on the driving style.
If its manual, do a 20mph fifth gear test. Cruise up to 20 or so, then go into fifth, and shift it going into full throttle immediately, like you were going from wot 2nd to wot 3rd. If the rpms are too high for that speed, or if your engine revs without a corresponding change in speed, the clutch is slipping. That is not a good test for high end slipping however, and the only other test I know is the infamous hill test. Other than getting it inspected and/or outright replacing it, and if you're not smelling any burning, I do not know a way to reasonably diagnose the problem.