ECU Tuning for N55 Engines

Tuning for the 3.0 Cylinder Inline 6- cylinder N55 Engine found in the BMW 1 series, 2 series, 3 series, 4 series and more.

Precision tuned for more power and better drive-ability.
Peak HP gain up to = 103+ hp
Peak Trq gain up to = 139+ ft-lbs
Price: $799.95


Decades of tuning for the street and track has helped Turner BMW Service understand what’s important to the BMW tuning community – highly effective, reliable, consistent performance tuning that heightens the BMW driving experience. In order to build on this success, our calibrator dedicated months of testing, tuning, and re-testing our 2015 F32 435i xDrive coupe on our in-house Mustang dyno to ensure we were delivering a tune that is compatible with bone-stock cars, while also offering the ability to capitalize on the additional engine power to be found through common modifications to exhaust, intake, and intercooling.

What modifications do I need?
We’re able to tune for a variety of popular modifications, and have structured our offering into several experiences:

Stage 1 – Great for stock cars, or those with an intake and/or exhaust upgrades such as a cat-back exhaust. We experienced massive peak gains of +96 horsepower, +127 ft/lbs torque on our test car with an an M Performance cat-back exhaust and Turner Motorsport intake. While both peak and max gain numbers are excellent, what’s really impressive (and what will benefit daily drivers and competition enthusiasts alike) are the consistent gains across the power band.

Stage 2 – For cars configured similarly to Stage 1, but with additional resistance to heat with the addition of a Turner Motorsport intercooler. We experienced similar max gains to Stage 1 with improved top-end power output. More importantly, with an intercooler, we were able to keep temperatures lower for longer versus without, which is especially important for cars driven hard, in hot weather, or anyone looking for more consistent power delivery. With this added resistance to heatsoak, additional performance is available, with peak gains over a stock tune of +103 horsepower, +139 ft/lbs torque – also with improved power and driveability across the powerband.

Stage 3 – For cars with high flow downpipes. Coming soon!

Our N55 tunes remove the factory speed limiter. All stages are designed to accommodate either 91 or 93 octane fuel – your car will compensate for lower octane, but will make more power with 93. Install more go-fast parts in the future? Give us a call – we can offer upgraded tune files to existing customers for a nominal charge. Starting from scratch and looking to upgrade as a single package? Click here.

Under light footed driving, our tune makes the N55 feel like a powerful naturally aspirated engine. Bury your foot, and on comes massive turbo thrust. The throttle pedal is excellently modulated, as a BMW should be, with the transition between vacuum and boost coming on effortlessly with ease of control. Even today’s modern piggyback tuner options can’t equal the driveability and smoothness of our ECU flash – you will be impressed with not just the impressive power increases, but as well the smoothness of the tune and significantly reduced turbo lag. Testing on our own development shop car illustrated we were still able to successfully set all emissions readiness flags in preparation for emissions testing.

How do I get my tune?
Easy, you can install the tune in your own garage or driveway, or have us do so by visiting our facility in Amesbury, MA. No wiring changes, no irreversible modifications, no need to even open the hood.

What else do I need to know?
Maintenance. The key to building a high performance machine is regular maintenance and upkeep. We’ve found regular ignition system service to be of significant importance – replace your spark plugs with a one-step colder version at 25,000 mile intervals for best results, and replace your ignition coils with every other spark plug replacement. Gap plugs to .020″ for best results. Give us a call and we can take care of that too once your car is here for tuning.

Dealer service. After tuning, there’s the possibility your local dealer may over-write your tune if they update your engine’s software. This simply requires reloading of the Turner tune after your service visit. We find many dealers to be accommodating of our software – simply letting your service adviser know your car has been tuned is often enough to avoid an unnecessary software update.

BMW warranty. Generally speaking, a car manufacturer cannot legally void your warranty for adding non-stock equipment – read more here.

We offer this tune and performance packages for the following models:
2014-2016 F22 BMW M235i M235i xDrive Coupe
2014-2016 F23 BMW M235i M235i xDrive Convertible
2012-2015 F30 BMW 335i 335i xDrive Sedan
2012-2015 F32 BMW 435i 435i xDrive Coupe
2014-2016 F33 BMW 435i 435i xDrive Convertible
2014-2016 F36 BMW 435i 435i xDrive Gran Coupe