[fsucoy]

There is very limited info and reviews on throttle mappers, so I thought I'd contribute my experience for reference.

Being a previous owner of a 2007 335i 6Spd Coupe, I fully understood that the F10 wouldn't compare in terms of performance to the 335i, and that it was designed specifically to be a more refined ride.

However, the throttle lag programmed in the F10 makes the car's response much more disappointing than the potential of the underlying power plant would suggest. More importantly, having a car that doesn't respond as expected when you need it is downright dangerous!

Following a few dangerous encounters where the car didn't respond when I needed it, I concluded that I finally had it and needed to address the throttle lag on my F10 535i!

Some may argue that a chip tune (e.g. JB4, RaceChip, etc) is a better option, given the increase in power, and would improve throttle performance.

However, I reached out to several reputable shops and specifically asked the following:
(1) If any chip tunes directly reconfigured the throttle mapping?
(2) If anyone at their shop had personal experience with throttle mappers, like the Sprint Booster, Remus Responder, etc?

All five shops that I contacted confirmed that while adjustments to the intake, timing, and overall HP increase indirectly add to the effect of improved throttle response, none of the chip tunes really configure throttle mapping.

I managed to find two shop employees that had personal experience with throttle mappers and they both confirmed that throttle mappers are, in fact, complimentary to a chip tune and really make a difference to the overall feel and responsiveness by solely improving throttle response - which was exactly what I wanted.

The primary options that found on the market are the Sprint Booster, Remus Responde, PedalBox, and RaceChip Response Control. There isn't a lot of experiential info available on any of them from the BMW community. But, I went with the Sprint Booster as they seemed to be the most established in the market and there are plenty of positive reviews on forums by other car makers.

The Sprint Booster is arguably the simplest of the all options. While the others have more available modes, the Sprint Booster simply has 3 modes, Race, Street, and Stock. The remote switch is also simple in design with one color LED button to toggle between the modes (Red = Race, Green = Street, Off = Stock). So, there's no need to meddle and you can easily see what mode you're in with one glance. Simple; I like simple!

Installation? Also very simple! 10 min is all it takes to install. Simply remove one bolt on the accelerator pedal, decouple the wire harness that connects to the pedal, insert the male end of Sprint Booster dongle into the pedal, and insert the wire harness into the female end of the Sprint Booster. You can get creative on where to run the wired remote switch. I ran it under my dash and into the drivers glove box for easy access as well as discretion.

As for first impressions, even though there is no actual power increase, the difference is incredibly obvious and it makes the car feel like all of the power that has been under your hood is finally woken up!

Make no illusions about what it is, and what it is not. This simply makes your car feel more responsive. It does not add any power.

The only reservation I had was the price. Do I think this is worth $300? No, I think a fair price would be in the $150-$200 range. However, it's hard to put a price on getting your car to finally feel like it drives the way one would expect from a BMW.

Bottom line, would I recommend? Absolutely!!

Whether you already have a chip tune, or whether you don't want to risk voiding your warranty by going with a chip tune, a throttle mapper like the Sprint Booster is a great addition to any setup that improves overall feel and response. This is how your F10 should drive and respond!

One word of caution regarding installation: be very careful and take note that the female end of the dongle has no indication of which way is the correct polarity when you plug in the male end of the wire harness into the Sprint Booster. There's a 50/50 chance to get it right and the only way to know whether you did get the polarity correct is when you start the car.

If it doesn't start smoothly right away, and the engine putters and dies - DO NOT KEEP TRYING TO START!!! If you do, you're ECU will throw an error code that you'll have to reset via an ODB2 reader.

Simply unplug the wire harness from the female end of the Sprint Booster dongle and turn 180 degrees to reverse to the correct polarity and you should be all good.

Best of luck and enjoy!