The standard key is for street driving, nice performance just a little better than a GT. The track key let's the beast out, 12.3 second quarter mile stock, 11.88 with a Steeda Cool air system. The track key adjusts over 200 parameters (cam timing, fuel control, spark maps, engine braking, etc.). Handling and steering are also effected. It handles like a dream when I put it through the paces during mountain drives. In a word ....COOL!!!!! I can only compare it to hanging on as the car jumps to please.