don't have a source, but a heads up............... everything I've read says that those chips mostly just fool the eng into thinking it's running cold, so the fuel mixture stays "rich". This yields a little more HP and slightly different shift points. You will loose some MPG. You may just want to consider a free flow air filter (K&N type) and new plugs/wires. Makes a big diff in performance if they are old or "cheapies". I'm talking about the $69 chips. The more expensive ones MAY yield maybe 10 more HP?