Does anyone know what this Free upgrade on the Power Commander website actually changes? I have been running mine with it on for over 2 years but I'm am curious if anyone has tested to see what it actually helps or does. Thanks!

I have an "old skool" PC3 so not "upgrade" for me.

I believe it enriches the mixture when you crack the throttle. If you wan't a more detailed explaination e-mail Dynojet's customer support. I am sure they can help you out.

You can actually find some write ups on the website. I like it. I went with the "average street rider" setting and noticed a nice difference.