To Whom It May Concern: I want to let you know how extremely happy I am that I achieved everything that you promised when I installed my AquaTune system on my '92 Ford Explorer with a 4.0L engine. Not only did I receive my 25% increase in fuel economy, I also received a very impressive horsepower gain. I would also like to tell you that prior to putting this system on, I used to have a serious blow-by problem. So much so that even my valve covers would leak oil from the excessive crank case pressure. This problem has now totally cleared up with this system, and no more leaking oil. I will be recommending your product to my friends. Thank you for such a fine product.