with such a light car 50 hp, has to make a significant improvement, in real world envoirnments. I have a friend at work with a mustang gt. It is the model before they went to the 3 valve engine, and he can hang, but not pass. It would just be nice to here before and after results. I could feel a difference just changing out the air filter on my cobra. which might have been 3-5 hp. chris