Jerry and Clint both think it is reading about 10% low. They had some work and new software put in and now it reads low, but it is very repeatable. My2006 LTD Roadster reads 199.6 RWHP. I think it is doing about 220RWHP. It was reading 195 RWHP and have done two mods since (K&Ns and 74mmTB) Thought I would get between 215-225 RWHP with those mods. Runs good. Will add 74mmMAF tube later, should see some increae there too.