• N55 tuning goes to the next level - Vargas N55 turbo upgrade with BMS JB4 tuning dyno results - 468 wheel horsepower

      Finally the N55 motor is getting some love! Up to this point the twin turbo N54 engine has dominated modern BMW turbo tuning and the N55 has been left in its shadow. BimmerBoost is proud to report that vendors BMS and Vargas Turbo Tech were able to work in collaboration and show a successfully tuned and installed turbocharger upgrade for the BMW N55. This is still very early on and there is more to come but N55 owners finally have a realistic turbo upgrade option to look forward to.


      Notes from Terry@BMS:

      I think the data speaks for itself but here are a few notes:

      1) Boost with the fix is overall what I expected it would be from the start. It's able to hit ~20psi in the midrange and hold ~18psi @ 6000rpm. There is probably another psi or so of midrange boost in there with a 3.5 bar MAP sensor if we want it. It makes a little less down low which is to be expected. The gains up top are now well worth anything lost. On the street it's spooling faster now and feels great.

      2) Tuning is done using JB4 ISO v5.2. We also reworked the back end flash for the E50 + meth fuel and found MBT around 9 degrees peak. The flash is loaded using a Cobb AP. Currently, they only support 2011-early 2012 models. Hopefully more models are added soon. The turbo can be used with the OEM flash but only with E85, or E85 + meth. We'll write pump gas maps for the turbo in the coming weeks for those who are using the back end flash and want to run 91 or 93.

      3) With a little more boost and some other tuning tweaks 500whp might be possible with this setup. For now I'm very happy to have 120whp over stock @ 6000rpm. At 468rw this car should have enough power to run mid 11s full weight. I hope to find out this weekend.

      4) This car finally lives up to it's "Dr N55" plates.







      This article was originally published in forum thread: Vargas N55 Turbo Upgrade Dyno - Take 2! started by Terry@BMS View original post
      Comments 143 Comments
      1. Sticky's Avatar
        Sticky -
        Terry! You linked to the images rather than manually importing for a cleaner look, I'm proud of you Click here to enlarge

        Ok so what I don't understand is why didn't the higher boost numbers give higher peak figures?

        I mean this is a new record although it only differs by a handful of hp and torque from what you hit previously.
      1. Terry@BMS's Avatar
        Terry@BMS -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Terry! You linked to the images rather than manually importing for a cleaner look, I'm proud of you Click here to enlarge

        Ok so what I don't understand is why didn't the higher boost numbers give higher peak figures?

        I mean this is a new record although it only differs by a handful of hp and torque from what you hit previously.
        There were questions about how the turbo might perform at higher boost levels so we cranked the boost up just to fully explore that area. Although the initial tuning wound up being close to where we'd like to run it at least now we know for sure. Click here to enlarge
      1. maxnix's Avatar
        maxnix -
        Yeah, unfortunately that will not work on the ECU used in the newer DME.