[baduncadonk]

Installed Sprintbooster "auto" model today. Here are observations:

1. No instructions came with the package. (I purchased from MiniMania.com). The lack of easy, graphic instructions for a consumer hop-up part costing $330 is irritating and reflects poorly on the manufacturer and its U.S. distributor.

2. The install was conceptually easy, but I had difficulty finding enough space behind the carpeting to comfortably hide the SB unit. I managed to push it down far enough to just barely reattach the the gas pedal unit, but it was not easy and I have lingering concerns that I may be over-stressing the SB unit with pressure from the reattached gas pedal box. If my car conks out unexpectedly in the future, I will definitely pull the SB first.

As for the performance of the SB, the resulting throttle behavior is interesting:

1. The pedal is indeed a bit more sensitive at low speeds, although you quickly get used to it.

2. The throttle behavior under spirited driving does appear to negate the frustrating lag that was present before. The throttle curve seems to be nicely linear from 25% to 100% pressure on the pedal.

Finally, I had a friend, who drives an '07 M5, take my car out before the SB install today. He was frustrated by the throttle lag and wouldn't shut up about it. I will have him retry the car tomorrow, with the SB added, to see whether his impression has changed.

Originally Posted by baduncadonk

Okay, so. . .

I ordered a SprintBooster yesterday--to much abuse and laughter from my business partner, who thinks the SB is a complete scam.

I am also inclined to not believe the hype, but I will install it this weekend and try to give an unvarnished review here. I do have noticeable throttle lag in my April-build 135i automatic.