I'm checking this one out...but it doesn't give me a good estimate of how much hp I will gain. Some cars gained up to 50 hp. However, others only 14hp. Any suggestions?
http://www.performancechipsdirect.com/BMW/1-Series/

http://www.performancechipsdirect.com/unlock-hp.html
I forgot to say make sure u get a look at those links to get an idea of what I'm talkin about.