I stumbled across this the other day. Looks like a great way to measure if those changes you made really helped without going to the track or the Dyno shop. I have heard good reviews of this product, but have not tried it. THis is a good price on it from what I have seen. Just passing it along to my fellow motorheads. If anyone has personal experience please share.

GTech Performance Meter

http://www.softwareandstuff.com/CES10539.html

Pat