I have just bought my 1st BMW, 2008 335xi coupe with sport package. I see this CF chip , claims 60_ HP increase and 4-7 mpg improvement...need some feed back has anyone tried this ?????? My dealer said they would put in but if something went wrong and could be asigned to the chip add on then my 100,000 mile warrenty could be effected , if they traced to the add on chip.....anybody know anything????
I haven't seen "CF" chip. JuiceBox, Dinan and others but not that. I very much doubt mileage gains. I certainly think you can get HP gains - the Performance Package reprogram from BMW gives you 20-30, Dinan gets you about 75, and you can go higher - but at the cost of reliability. All re-programming loses you warranty; Dinan is the only one that has worked with BMW to cover warranty issues related to their tune.
I have heard from a guy at a dealership that they can not tell if you have the chip or not if you pull it out before taking the car in, hence no risk of voided warranty. -Bartek-
