The Z8 software was installed yesterday. Of course, I could just have easily been on the receiving end of some great ruse and had nothing changed -- and would probably be writing the same impressions since I really want to believe there is a noticeable difference.
Bottom line: Sport mode now feels as much improved over the pre-Dinan Sport mode as the pre-Dinan Sport mode did over the pre-Dinan non-Sport mode (got that?). Feels like getting about one-third of a gear better response throughout the rev range. Would love to say it feels like a full gear but that's just such an unrealistic expectation. But even one-third of a gear improvement, if one really thinks about it, is pretty darn good. The net effect is that the Z8 feels like it has slightly shorter gearing but the car is actually getting a slightly higher maximum speed in each gear. No before / after #'s, such as in-gear acceleration. Impression is all seat of the pants.
Per the Dinan Web site: "While we can not [sic] offer the typical increases in horsepower and torque you have come to expect from Dinan, there is still plenty to be gained from Dinan Performance Engine Software for the new Z8. For example, the software raises the factory rev-limit by 300 rpm, endowing your Z8 with a broader power band and greater road speed in each gear. The Dinan software also removes the factory top speed governor, providing the Z8 with top speed potential that approaches 200 mph! [The dealer service techs said top speed is actually now in the low 170’s.] This is certainly not to suggest that you should operate your vehicle at such high speeds, but it is nice to know you can. In addition, reprogramming the Z8's 'fly by wire' throttle system enabled us to speed up throttle response, as well as eliminate the 'dip' in the power curve that occurs just off of idle." The Dinan site simply substitutes the term "M5" for "Z8" in describing the M5's software upgrade; everything else is verbatim. I inquired and the software is indeed the same as that used on the M5.
It is a half-hour process from start to finish. The Dinan software is already installed on the dealer’s Windows CE handheld device; in this case, it was an HP Jornada with the clamshell style design. First, the Z8's 3 DSC fuses (which also control ABS) are disabled, the CE handheld is then wired to the Z8's CPU and completes the software upload in about 10 minutes. After uploading, the CE is disconnected from the Z8 and the DSC fuses are enabled again. The service techs then fire up the car, do a few simple tests (e.g., rev the engine, disable and enable the in-car DSC button) and then I was on my way home. There is a now a permanent record of the software in the BMW and Dinan databases, as well as a sticker located by the car’s CPU / fuse box indicating that Dinan software is installed.
The work was done at BMW Gallery, a Dinan authorized dealer, in Norwood, MA. They were very friendly, professional, and accommodating.
- A-Train