Depends on what model year your car is. '95's (OBD-I) respond extremely well to the Sharkster. '96 and later (OBD-II) cars respond in very different ways. Check the archives. You'll see people claim rocket-sled acceleration, and you'll see folks claim a LOSS of hp, and you'll see everything in between. Most people say it is a POS, though. please tell me more in the market for a chip i heard this was the best one. how so?