One of the greatest values of the Accessport is the ability to easily update and apply revised maps to any car at any time with free firmware updates. This convenient Accessport feature is part of what motivates our calibration team to consistently improve OTS maps and updated Accessport features as our knowledge and experience with each platform increases. With that in mind, our Porsche team took the opportunity to spend a day at COTA with 4 different variations of the 991.2 platform to put our most recent map revisions to the ultimate test and they passed in literal red, white, and blue colors!
What and Why?
The underlying logic for modern Porsche’s is to target a specific engine load value based on pedal input by using various systems related to boost, ignition, and airflow management to achieve that goal. As a result, the ECU is very active over time and dynamically responds to changes in temperatures and fuel quality. Generally, that is a positive thing as it allows the car to be adaptive and safe but the downside is that it can also produce progressively declining power and performance over time if the balance between aftermarket changes and OEM logic is not managed properly when tuning.
Keeping that in mind, we’ve made several subtle but highly effective adjustments to further strengthen that balance. In the past, in order to achieve significantly higher than stock torque requests, the turbos would tend to make very high boost pressure which was effective at increasing power but would also produce excessive temperatures and knock events that would ultimately result in lost power and consistent response over time. So, producing the same increases in power while avoiding the eventual decline was the end game of this update.
In order to achieve that goal, we were able to expose a few helpful OEM tables that Porsche normally does not make use of on these cars. These tables allowed us to apply temperature specific limiters that enhance the car’s reactive capacity to deliver consistent torque across a range of conditions and temps. What that ultimately means is that higher torque requests are still attainable with more consistent boost behavior and limited ignition corrections even in extreme driving scenarios.
All about the Data
Naturally, most of the development was done on a computer, dyno, and on the street. So the final test was to torture the cars on the track. And what better place to do that than at your humble neighborhood Formula 1 circuit.
To cover our bases we rolled out a Turbo, Turbo S, a Carrera S, and a pretty red 3.0T. The cars were lightly prepped with new pads, fresh fluids, and mostly stock setups aside from intercooler and exhaust upgrades on the Carrera S, and of course the latest OTS Accessport maps flashed to the ECU of each.
As mentioned before, the major goal of the updated calibrations is to provide consistent and usable power gains that persist even when pushing the cars to their limits. Despite being mid-December, the weather was quite warm, reaching into the 80’s by mid-afternoon. Which was a good thing as it ensured that the results wouldn’t be skewed by unrealistically low intake temps that would be great for performance but wouldn’t serve as well for the purpose of proving the value of the temperature based map updates.
After each session, the cars came back to the trailer and we reviewed datalogs from the Accessports. The results were exactly what we hoped to see:
– Ignition correction stayed within acceptable ranges even after repeated hot laps.
-Boost was consistent across all temp ranges.
-Adaptive ignition maintained full octane. (essentially meaning that the car did not feel the need to automatically adjust ignition timing as temps increased)
-Cars stayed cool on track (IATs consistent with new power).
-Tranmissions shifted consistently in auto and manual modes.
Also, all four cars were able to achieve repeatable times in the 2:30 range. Those aren’t record-breaking laps but the track was full with dozens of cars in each group, so the opportunity for uninhibited sessions wasn’t possible. Never the less, laps in the 2:30 ballpark are quite quick and the ability to achieve those times on street tires without seeing any substantial decreases in speed as the day progressed was great evidence that the improvements made to the tunes worked just as well on track as on the dyno or street.
To make sure you have the latest and greatest maps for your 991.2, update your Accessport firmware on your Windows or Mac computer with Accessport Manager. Then make sure to use the Tune then Change Map function on the Accessport to flash the most current version (v1.06) to the ECU in just a few minutes, and don’t forget to check for updates regularly as we will certainly make more improvements in the future!
CLICK HERE for Porsche 991.2 Turbo/Turbo S Map Notes with dyno graphs and more details.
CLICK HERE for Porsche 991.2 Carrera Map Notes with dyno graphs and more details.