What I have read all over plus asking garages the maping with chip mod is not that great. You have to add cat modifications besides so for 2500 to 3500 you will realize gains of maybe 20 hp at best. There is a penalty in the lower rpm's. After all is said and done the only way to go is to supercharge the engine which will run over $ 5,000 US. The increase will be of 30% which is about 60 hp in a 2003 S which is what I have. I believe you also have to change the cats to accomodate the modifications. That is the only way I see doing anything. The engine swap is more expensive. In short I think we should be happy with the engine and the dynamics of the car we own. The hp race is extremely expensive for this car.