OK... everyone thinks that these are "BAD" blowers... they are not bad... i know of someone making close to 450 RWHP on this blower that Brian tuned... You get what you paid for though... if you want to be around the 350 whp range (with fuel ungrades) and run the car safe they are not bad blowers... they are almost maintanance free, no oil required, no taping in the oil pan, very quiet, takes about and hour or two to install, but the bad part about is that you can't ungrade them and the most boost you can push is about 9psi... for the money that they are selling used, they are not bad... They are a very street friendly blower for a mild application... Compared to a Vortech, Paxton or a Procharger they dont do so well but you are going to pay a lot more for either one of them three... But like i said, for the price, they are not bad blowers, but it you have 500+ hp in mind than look into another blower, or spray it too on top of the Powerdyne... But if your goal is no ore than 350-400 whp on a stock(ish) 5.0 than it's a good blower to have...