I didn't dyno my car, but this isn't some magic solution that gives you horsepower. That being said, this is a great engine additive. The engine seems to run a lot smoother and quieter. There's a lot less random ticking and general drama in the engine. It's quiet to the point, where my wife, who isn't into cars, noticed how much the engine is.I do notice that I am getting about .5 mpg average. Whether or not that's worth it is up to you. It is a bit pricey.