991 Twin Turbo 

Table Descriptions and Tuning Tips
Version 1.0 

Date Revised: 12/11/2015 

Tuning Guide and Table Definitions

This tuning guide is broken into the basic components of tuning a Porsche 991TT and the tables associated with each of these components. The guide outlines basic tuning strategies and defines tables for each major tuning category, such as boost control, fueling, and ignition timing.

Step 1 – What is the mechanical configuration of the vehicle?

The first step in tuning a Porsche 991TT is choosing a COBB Tuning Off-The-Shelf (OTS) calibration that most closely matches the mechanical components and modifications of the vehicle to be tuned
The Stage1 calibrations are designed for vehicles with no aftermarket parts at all. The Stage2 calibrations are designed for vehicles with an upgraded exhaust system. This major difference in configuration impacts the pumping efficiency of the motor and critically impacts all major aspects of tuning (boost, fuel, and ignition).

Step 2 – What fuel is the vehicle using?

Note that COBB Tuning offers calibrations for four different fuels: 100 octane (105 RON), 93 octane (98 RON), 91 octane (95 RON), and ACN91. Higher octane ratings indicate higher quality fuel that burns more slowly and can support higher cylinder pressure. This difference in fuel will determine how the car is tuned. Higher octane fuels support more ignition timing, higher boost levels, and leaner air-to-fuel mixtures compared to lower octane. Using a map designed for high octane with low octane fuels can result in damage to the motor.

Step 3 – What type of air intake is on the vehicle?

The 991TT utilizes a calculated mass airflow, but does not use actual MAF (Mass Air Flow) sensors. It uses airflow calculations to estimate engine mass air flow. Changing intakes will require some small changes to the calibration, but because the car does not have MAF's it is not as important to rescale the MAF based on intake pipe diameter change. The 991 Turbo does use the airflow calculations to limit boost pressure, so making changes to calculated airflow tables is critical to making the car run correctly.

Step 4 – Calibration refinement on a chassis dynamometer.

A: Perform initial testing at low boost.

After selecting the most appropriate initial calibration, prepare to test and refine the calibration on a chassis dynamometer. When creating a custom tune, it is best to begin testing under low load conditions by lowering the target torque and airflow tables. You will also want to lower the Pressure Up Throttle Setpoint table, as this is that target pressure before the throttle plate, the car is going to target.

B: Connect the Accesstuner software to the Accessport equipped 991TT

Open the selected starting calibration in the Accesstuner software then configure the Accesstuner software to connect to your vehicle. Attach the OBDII connector to the vehicle and, to your Accessport (if applicable), then connect the associated USB cable to your computer. Press "Ctrl+F" to configure the program. Select the directory in which to store your data logs under the "Logging" tab.

C: Log critical engine parameters while testing.

Accesstuner software allows the user to sample and record critical engine parameters including sensor information and commanded engine function. Open Accesstuner and load the calibration currently flashed to the vehicle. Attach the OBDII cable to the vehicle and the computer. Press "Ctrl+F" to configure the logged parameters in the "Log List" tab, and those displayed in the Accesstuner "Dashboard" through the "Gauge List" tab. The Dashboard, a screen that reports active engine and sensor parameters, can be accessed by pressing "Ctrl+B." It is critical to actively monitor the condition of the motor during tuning and this screen is the single best way to do so. These data monitors allow the tuner to determine if a calibration is performing correctly. Accurate and deliberate assessment of logged parameters is the only way to avoid conditions that may damage the motor.

The 991 Accessport can log 25+ parameters around 40 Hz, The amount of parameters selected does not impact the logging speed.

D: Tuning for appropriate Air to Fuel Ratios (Lambda)

The ideal air to fuel ratio (AFR) depends upon fuel quality, engine design, fueling model (port injection, DISI, diesel, etc.), heat exchanging abilities, and other variables. Higher octane fuels are more stable at higher cylinder pressures, and are more resistant to pre-ignition. Leaner AFRs can produce higher power, but also create more heat that may lead to unsafe pre-ignition. Lower octane fuels, such as 91(95 RON) and ACN91 (Arizona, California and Nevada 91 octane), are less resistant to detonation and require a richer (fewer parts air per parts fuel) AFR for safer operation. Richer AFRs produces less heat, protect against detonation due to a cooling effect of the excess fuel and usually produce less power. We have found that the 991TT motor is tuned on the leaner side from Porsche. After some initial testing we have found that just by richening the fuel target, the car picked up power. So we suggest a target AFR of 11.8:1 or a Lambda of around .80.

Air to fuel ratios for these vehicles are directly impacted by several tables. The Porsche fuel control system operates a closed loop control strategy. This means that the car runs a set of wideband air fuel sensors, and is constantly adjusting the fuel targets based on a collection of variables. The fuel target under wide open throttle is dictated by the Basic Lambda Setpoint maps as well as Lambda Full Load Enrichment and Lambda Full Load Enrichment for Sport Mode. Setting a target in this table will yield the desired Air Fuel desired, as long as some of the others conditions are correct.

A fuel mixture that is too lean will contribute to uncontrolled combustion, excessive heat, detonation and possible engine damage. The objective is to run the car at the richest air to fuel mixture possible that does not sacrifice power. Ultimately, the best air to fuel can only be determined in concert with changes to ignition timing. For example, in some cases a comparatively rich air to fuel mixture can be run with more ignition timing than a leaner mixture. This combination may produce higher power than a lean mixture with less ignition timing. Generally speaking, the air to fuel and ignition timing combination that produces the best power while minimizing heat is the desired calibration. Of course, this ideal is not limited to ignition timing and fuel, but is also a balance of variable cam timing and boost pressure.

E: Tuning Ignition Timing

The ignition control strategy in the Porsche 991TT is very dynamic and has a lot of contributing variables to determine the overall ignition timing value. Since the car is always trying best to calculate an overall best efficiency, it does this for ignition timing by using the Absolute Calibration for Reference Ignition Angle Due to Valve Overlap and using a target lambda (ʎ) =1 as a base for the efficiency. Additive corrections get made and it forms a variable in the ECU that is "optimal timing." This is the basis for all the ignition calculations in the car. The Porsche uses a strategy of two states of cam timing as well. These points will dictate which of the ignition timing maps are used and when. The actual ignition timing uses some additional variables and then comes to the conclusion of ignition timing based on the difference between Absolute Calibration for Reference Ignition Angle Due to Valve Overlap and Calibration for Reference Ignition Angle Due to Valve Overlap. Ignition Timing changes will need to be made in the Calibration for Reference Ignition Angle Due to Valve Overlap tables to start, as these are the basic tables that will reflect changes made. The first 4 tables are the main tables being used in WOT (0-0 thru 0-3).

F: Knock Control System

The knock control strategy on the Porsche 991TT is very complicated and uses individual cylinder knock control to make changes to the ignition timing at all times. The system is very sensitive and thus almost always has some sort of feedback. You can monitor knock retard and ignition correction in each cylinder. This is the best way to check for detonation, and to ensure a safe running vehicle. The closer to 0 the better, but if it sways into the negatives (-1 and below) this is the car registering detonation. Since the car is very dynamic it is made to be sensitive. If you are getting values past -6 you will want to try and lower ignition timing, or add more fuel to try and see if you can bring the values back closer to 0. Running a race fuel will also help in getting the knock control values closer to zero.

If running built engines you can change the knock detection thresholds in the software. By raising these tables you are de-sensitizing the knock control system. THIS SHOULD BE DONE WITH GREAT CARE AS DOING THIS CAN RESULT IN ENGINE DAMAGE AS KNOCK CONTROL BECOMES LESS ACTIVE!!

Generally speaking, higher ignition timing supports higher torque and greater power. However, ignition timing should be increased with great caution. Higher timing yields are limited by fuel quality and the mechanical limitations of the motor due to higher cylinder pressure. Too much timing will produce knock sums when fuel quality is the limiting factor. When fuel quality is high, ignition timing should ONLY be added when its addition produces a substantive increase in torque and power. If increased timing does not increase torque, the extra cylinder pressure is simply producing unnecessary stress on engine components.

G: Porsche Torque Control Strategy, Boost Control and VTG Control

The Porsche Siemens SDI9 uses torque control to influence how the car behaves on power and off power. This system uses input from a wide variety of internal variables and external sensors to dictate how the car reacts in certain conditions. The boost control system works in this same manner, not by trying to use a "standard" boost control setup, but by trying to achieve a target torque value. This is dynamic and varies based on conditions, temperatures etc.
This ECU uses various methods to control torque output, such as closing the throttle plate when the car overshoots a target torque table. So you will always want to monitor throttle plate opening as it is a way for the car to lower the torque output. Other methods include lowering ignition timing, or changing air fuel ratios. So you want to be sure that the car is optimally calibrated in all conditions.

From the factory the Porsche 991TT is equipped with VTG turbo chargers. These turbos are a bit different than the traditional turbo chargers most are used to. Manufactured by Borg-Warner, these turbos don't use a standard wastegate to control the boost pressure regulation but instead control turbo pressure by channeling gas flow in the turbo by adjusting guide vanes. It can change the angle of these guide vanes thus it's able to change the geometry of the turbo chargers. It can maintain a turbo pressure earlier and can hold that pressure throughout the whole torque range.

This control rhetoric is implemented by the ECU and changes boost pressure to meet the torque targets set in some of the tables. There are also some VTG tables that will directly affect the boost pressure control such as Turbine Setpoint Position for Sport Mode and Turbine Setpoint Position for Normal Mode.

The ECU does use a target PSI based boost system as well to try and control boost before the throttle plate. This table is called Pressure Up Throttle Setpoint. This is a target boost pressure and should be raised if you are trying to increase the boost pressure. The target pressure can be logged, and should be when trying to increase boost pressure. The boost pressure cannot be raised if the Maximum Airflow tables are not high enough! If you increase the PUT tables and the boost does not increase it is more than likely due to the Maximum Airflow tables not being high enough. The Y axis of this table is MAP Setpoint, so it is a correlation of boost pressure before and after the throttle plate.
The 991 TT also uses an estimated turbo speed setpoint. Although the car does not have actual turbo speed sensors on the compressor of the turbo, it uses a calculation to estimate the turbo speed. In order to raise target boost pressure you will need to raise the max limits of the turbo speed tables in order not to trigger any errors.

Another very important part of the control system for boost control is calculated airflow by the ECU. The ECU will limit boost pressure based upon the calculated airflow the car is seeing. There are 4 tables that are very important to being able to effectively raise boost pressure. They are Maximum Intake Air of the Engine at Standardized Ambient Pressure, Maximum Intake Air of the Engine at Standardized Ambient Pressure Sport Mode, Maximum Intake Air of the Engine at Standardized Ambient Pressure in Sport Mode – Map Setpoint Limitation, and Maximum Intake Air of the Engine at Standardized Ambient Pressure – Map Setpoint Limitation.

Since the ECU does not have mass air flow sensors it uses estimated airflow. You will want to raise these values with caution as the car is able to make large amounts of boost on the stock turbo's, which can cause engine damage.

H: Tuning Variable Cam Timing (Vario-Cam Plus)

Porsche uses a variable cam timing system that changes cam duration at different engine speeds, but with Vario-Cam it also changes the valve lift dependent on cam phasing. This provides very good efficiency in all driving ranges as it can change lift using hydraulic tappets with a type of attachment pin. There are 3 lobes on the cam and the center is the "slow lift" the outer 2 lobes are the fast lift and pertain more to making more power and a higher lift. This helps to make more power through the power band.

The cam timing can be changed in the software. In order to see results from this type of tuning a chassis or engine dynamometer is required.

I: Speed Density/ Estimated Mass Flow

The Porsche 991TT does not use MAF sensors, but instead uses calculated airflow using variables calculated from sensors and other parameters in the ECU. It then uses these types of calculations to estimate the amount of airflow entering the motor based on the engine displacement and a slew of other variables related to air flow, temperature and barometric pressure. It does calculate a volumetric efficiency slope and offset. So while the ECU does no use a traditional speed density strategy, it uses a type of pseudo MAF/ SD setup using calculated variables and measured airflow into the motor through the PUT sensor and the MAP sensor.

If stroking a motor, the software allows you to enter the new displacement of the engine if changed, and the car will make changes to the mass flow calculations to allow for the displacement change. Tuning will still need to be performed, but the calculation will be as correct as possible. This table is called Engine Displacement.

The SDI9 ECU also uses heavy torque targeting methods. Most of the boost control is done by trying to achieve a target toque value and a mass flow that is calculated by the ECU. This target is very important, and being too far over or under can cause the car to have errors. The correct torque values are also important as they dictate shifting and the amount of power to the clutch's that may be too much or too little.

J: Integrating all tuning parameters for the ideal calibration

The ideal calibration for your Porsche 991TT is a combination of all major tuning areas outlined above. Generally speaking, the Porsche 991TT will make the most power when it runs a lean AFR with the maximum amount of ignition timing allowed by the ECU without detonating. However, the theoretical ideal air to fuel ratio and high ignition timing is not realistic for all configurations and fuels. Calibrations should be thoroughly tested on a chassis dynamometer, where the impact of tuning is easily measured, to determine if they are ideal for the vehicle, its mechanical components, and its fuel. For example, addition of ignition timing that does not result in increased torque is not ideal because it produces additional stress on engine components without a perceivable benefit. The same is true of boost and air to fuel ratio. If the vehicle can operate at a richer air to fuel ratio without losing power, it is ideal to do so. If increasing boost does not yield considerable power gain, the turbo may simply be out of its efficiency range and, in this scenario, less boost is actually more power. For a basic idea of ideal tuning parameters for your fuel type and mechanical configuration, examine the COBB OTS map notes.

K: Precautions:

Boost – The stock turbo chargers can produce boost levels in excess of 25 psi, which is enough cylinder pressure to cause engine damage if not tuned correctly. Be cautious when adjusting boost control parameters, particularly when any mechanical components of the boost control system have been altered from the factory configuration.

If using non-factory turbo chargers you will be required to run an aftermarket boost controller as the factory ECU has no way of accurately controlling a standard wastegate. The output from the ECU is around 250 Hz and standard boost control solenoids are generally around 30 Hz, so you will want to run an electronic boost controller of some kind.

Fuel – The stock fuel system in the 991 Turbo is Direct Injection. Therefore the fuel is injected directly into the cylinder at very high fuel pressures to help atomize the fuel. There are limitations to these systems, so you will want to measure fuel pressure to see if you are having any issues with fuel delivery.

Folder: Airflow Tables

Correction Factor for the Maximum Intake Air Depending on the Intake Air Temperature

Table Description – This is a maximum airflow table based on intake air temperature.

Tuning Tips – Raise this table if you don't want the throttles to close when intake air temperatures get high.Precautions and Warnings – None at this time.

Maximum Allowed Airflow Setpoint

Table Description – This value is the max amount of airflow allowed measured in mg/stroke.

Tuning Tips – This value is set high on the factory calibration. It is unlikely it will need to be raised unless the car is heavily modified (Turbos, Built Motor, etc…)

Precautions and Warnings – None at this time.

Maximum Intake Air of the Engine at Standardized Ambient Pressure

Table Description – This is a maximum airflow table based on calculated airflow, in normal mode.

Tuning Tips – Raise this table when tuning to make sure that boost pressure comes up. Since the ECU uses a calculated airflow target directly affect the maximum amount of allowed boost pressure.

Precautions and Warnings – None at this time.

Maximum Intake Air of the Engine at Standardized Ambient Pressure Sport Mode

Table Description – This is a maximum airflow table based on calculated airflow, in sport mode.

Tuning Tips – Raise this table when tuning to make sure that boost pressure comes up. Since the ECU uses a calculated airflow target directly affect the maximum amount of allowed boost pressure.

Precautions and Warnings – None at this time.

Maximum Intake Air of the Engine at Standardized Ambient Pressure for Different Valve Lifts 0 and 1

Table Description – This is a maximum airflow table based on calculated airflow.

Tuning Tips – Raise this table when tuning to make sure that boost pressure comes up. Since the ECU uses a calculated airflow target directly affect the maximum amount of allowed boost pressure.Precautions and Warnings – None at this time.

Folder: Boost Control Tables

Subfolder: Thresholds

MAP Sensor Out of Range Diagnosis – Maximum Threshold

Table Description – This value is the absolute pressure ceiling for range diagnostics for the MAP Sensor. Above this ceiling MAP sensor errors will not be reported.

Tuning Tips- This value should not need to be adjusted unless increasing boost.Precautions and Warnings – None at this time

MAP Sensor Out of Range Diagnosis – Minimum Threshold

Table Description – This value is the absolute pressure floor for range diagnostics for the MAP Sensor. Below this floor MAP sensor errors will not be reported.

Tuning Tips- This value should not need to be adjusted unless under extreme vacuum at high elevations.

Precautions and Warnings – None at this time

Maximum Allowed MAP Setpoint

Table Description – Maximum allowed MAP setpoint.

Tuning Tips- You will want to raise this if raising boost past the MAP setpoint.

Precautions and Warnings – None at this time

Maximum Engine Speed Threshold for Plausibility Diag Full Load

Table Description- Maximum engine speed for the diagnostic plausibility threshold at full load.

Tuning Tips- Raise this if you are having a plausibility error at full load for the boost control system.

Precautions and Warnings – None at this time

Maximum Manifold Air Pressure Value to Determine Engine Load Ratio Scale for Misfire Detection

Table Description- Above this psi value the ecu will no longer use engine load ratio scale to detect misfires

Tuning Tips- None at this time.

Precautions and Warnings – None at this time

Maximum Manifold Pressure to Limit Maximum Manifold Pressure to Limit MAP Correction

Table Description- Above this value corrections based on MAP sensor readings are disabled.

Tuning Tips- None at this time.

Precautions and Warnings – None at this time

Pressure Up Throttle Sensor Out of Range Diagnosis - Maximum Threshold

Table Description- Max value before tripping a diagnostic overboost error.

Tuning Tips- Raise this value if increasing boost pressure to be sure there are no errors.

Precautions and Warnings – None at this time

Threshold to be Reached Before Permanently Activating Load/TPS Plausibility Error

Table Description- Raw value, above this value the Load/TPS errors will occur. 

Tuning Tips- Try raising this value if you are getting Load/TPS errorsPrecautions and Warnings – None at this time

Folder: Boost Control

Subfolder: Torque Tables

Delay Time for Activation of Torque Limitation due to Ignition Retard

Table Description- Time delay of the torque limitation once there is a constant ignition retard.

Tuning Tips- Increase if you are planning on raising the requested torque at the clutch so that you do not fight a torque reduction.

Precautions and Warnings – This is a safety system that can helpful. Change this only if needed!

Indicated Engine Torque at Reference Conditions 0 and 1

Table Description- These tables are used to output a torque reference based on Airflow and RPM

Tuning Tips- None at this time.

Precautions and Warnings – These tables are what report torque, changing these will impact any other table that uses reported torque for a reference.

Map for Gear-Dependent Correction Factor for Torque Offset for Overboost

Table Description- Multiplier table that will limit overboost in each gear.

Tuning Tips- You can use this table to limit torque in each gear. Could be helpful if trying to keep traction in lower gears.Precautions and Warnings – None at this time

Map for Torque Limitation at Clutch for Overboost, Higher Limit Value in Sport Mode

Table Description- This is a target torque value. Raising this table is necessary to increase power in Sport mode.

Tuning Tips- The SDI9 uses a torque based strategy at controlling boost pressure. In order to achieve consistent increased boost pressure you will need to tune this tables accordingly. If tuned correctly you should be able to have the car meet these torque goals and use them as limiters still.

Precautions and Warnings – None at this time.

Map for Torque Limitation at Clutch for Overboost, Lower Limit Value in Normal Mode

Table Description - This is a target torque value. Raising this table is necessary to increase power.

Tuning Tips - The SDI9 uses a torque based strategy at controlling boost pressure. In order to achieve consistent increased boost pressure you will need to tune this tables accordingly. If tuned correctly you should be able to have the car meet these torque goals and use them as limiters still.

Precautions and Warnings – None at this time.

Max Requested Torque at Clutch to Activate Torque Reduction

Table Description- Maximum torque value at the clutch to start to reduce the torque as to protect the car.

Tuning Tips- Increase if you are planning on raising the requested torque at the clutch so that you do not fight a torque reduction.

Precautions and Warnings – None at this time.

Maximum Torque Depending on Intake/Ambient Air Temperature

Table Description- Torque limiter based on intake air temperature and ambient air temperature.

Tuning Tips- Raise this to be sure not to hit it as a limit.

Precautions and Warnings – None at this time.

Maximum Torque Limitation at Maximum Torque Limitation at Clutch for Overboost in Sport Mode 1 and 2

Table Description- This is a target torque table. Raising this table is necessary to increase power in sport mode.

Tuning Tips- The SDI9 uses a torque based strategy at controlling boost pressure. In order to achieve consistent increased boost pressure you will need to tune this tables accordingly. If tuned correctly you should be able to have the car meet these torque goals and use them as limiters still.Precautions and Warnings – None at this time.

Maximum Torque at Clutch due to Torque Limitation Depending on Gear Ratio by Auto Trans

Table Description- Maximum torque value at the clutch for a car equipped with an auto transmission.

Tuning Tips- Increase if you are hitting a torque limitation.

Precautions and Warnings – None at this time.

Maximum Torque at Clutch due to Torque Limitation Depending on Gear Ratio by Manual Trans

Table Description- Maximum torque value at the clutch for a car equipped with an auto transmission.

Tuning Tips- Increase if you are hitting a torque limitation.

Precautions and Warnings – None at this time.

Maximum Torque at Clutch due to Torque Limitation Depending on Gear Ratio by Manual Trans AWD

Table Description- Maximum torque value at the clutch for a car equipped with an auto transmission.

Tuning Tips- Increase if you are hitting a torque limitation.Precautions and Warnings – None at this time.

Minimum Value for Torque Limitation Due to Ignition Retard

Table Description- This table is the lowest amount of torque that the engine will be dialed down to when knock is present. E.g. If the car is pulling -2* of timing at 5000RPM the lowest torque of 538.427ft/lbs can be reported on the stock map.

Tuning Tips- None at this time.

Precautions and Warnings – None at this time.

Setpoint Mass Airflow Depending on Slow Torque Setpoint (VVL position Selective) 0 and 1

Table Description- Target mass airflow that the car will try to achieve vs torque.

Tuning Tips- Raise this value if you want to increase power, as this table has a direct correlation with the target torque strategy.Precautions and Warnings – None at this time.

Torque Limitation for Turbocharger Protection Based on Boost Pressure Actuator

Table Description- Maximum torque allowed when turbocharger protection is active.

Tuning Tips- This table is unused (maxed out) from the factory but can be set up to pull torque if turbocharger protection is active.

Precautions and Warnings – None at this time.

Torque Offset for Overboost

Table Description- Amount of torque increase allowed to be added when in overboost mode.

Tuning Tips- Raising this when raising the power levels in sport mode will allow for a further allowable increase in torque when in sport modes. You will likely need to raise this table when increasing Adjustable Threshold for Allowed Pressure Up Throttle Difference in Overboost.

Precautions and Warnings – None at this time.

Torque Setpoint Threshold if Turbo Protection is Active

Table Description- This is the target torque vale if the Turbo Protection is activated.

Tuning Tips- If you think that you are fighting with a torque setpoint that is too low you can try and raise this value to see if it is in turbo protection mode.Precautions and Warnings – None at this time.

Folder: Boost Control Tables

Adjustable Threshold for Allowed Pressure Up Throttle Difference in Overboost

Table Description – This table is the max allowed boost pressure increase in Sport modes.

Tuning Tips – If raising this value be sure to raise Torque Offset for Overboost as well.

Precautions and Warnings – None at this time.

Calculated Calculated Turbocharger Speed

Table Description – Table that calculates turbo speed.

Tuning Tips – Should not need to be modified for stock turbos.Precautions and Warnings – None at this time.

Constant for Maximum Pressure Up Throttle in Throttling Mode

Table Description – Calibrate able constant for the PUT boost control system when going full throttle. Changes to this should not need to be made unless you are having issues with the PUT system.

Tuning Tips- None at this time.

Precautions and Warnings – None at this time

Maximum Allowed Pressure Up Throttle During Torque Limit-Turbo Protection

Table Description – Maximum PUT when the torque limit is active for Turbo Protection.

Tuning Tips- Raise this if you think that you are hitting turbo protection.

Precautions and Warnings – None at this time

Maximum Charge Air Pressure Quotient for Charge Air Pressure too High Diagnosis

Table Description – This is a boost limiter. It needs to be raised if increasing boost pressure.

Tuning Tips- None at this time.

Precautions and Warnings – None at this time.

Maximum Difference Between the Two Pressure Sensors at Full Load-MAP

Table Description – Max delta between MAP and PUT sensor.

Tuning Tips- Raise this if you are going to be increasing boost as to not have errors from the deviation.

Precautions and Warnings – None at this time

Maximum Difference Between the Two Pressure Sensors at Full Load-PUT

Table Description – Max delta between MAP and PUT sensor.

Tuning Tips- Raise this if you are going to be increasing boost as to not have errors from the deviation.

Precautions and Warnings – None at this time

Maximum Setpoint Position for VTG Actuation in Dynamic Pressure Up Throttle Control Base

Table Description – Map for VTG requested based on estimated load.

Tuning Tips – This is a maximum control table. Raise this the VTG control is being capped by this table.

Precautions and Warnings – None at this time.

Maximum Setpoint Position for VTG Actuation in Dynamic Pressure Up Throttle Control Optimum Response

Table Description – Maximum setpoint for the VTG's based on load.

Tuning Tips– This is a maximum control table. Raise this if the VTG control is being capped by this table.

Precautions and Warnings – None at this time

Maximum Setpoint Position for Maximum Setpoint Position for VTG Actuation in Dynamic Pressure Up Throttle Control Base Sport Mode

Table Description – Map for VTG requested based on estimated load in sport mode.

Tuning Tips – This is a maximum control table. Raise this if the VTG control is being capped by this table.Precautions and Warnings – None at this time.

Maximum Turbocharger Speed

Table Description – Maximum allowed turbo charger speed before turbo protection turns on.

Tuning Tips – Raise this if you are increasing boost pressure to avoid boost issues. The ECU uses an internal calculated value to determine turbo speed, and so when raising boost pressure it needs to be raised to not hit any limiters.

Precautions and Warnings – None at this time.----

Maximum Turbocharger Speed Setpoint for Turbocharger Protection

Table Description –Maximum turbo speed setpoint.

Tuning Tips – Raise this table if increasing boost pressure to ensure that no errors are triggered.

Precautions and Warnings – None at this time.

Maximum Turbocharger Turbine Actuator Position for Stationary Operation

Table Description – The maximum VTG actuation while the vehicle is stationary.Tuning Tips – None at this time.

Precautions and Warnings – None at this time

Pressure Up Throttle Setpoint

Table Description – Boost pressure before the throttle plate target pressure.

Tuning Tips- Set this to the target value that you would like boost pressure to achieve, before the throttle plate. This is the target boost pressure that the car will try and achieve. Combined with the airflow tables this is the main table used to raise and lower boost pressure. Precautions and Warnings – None at this time.

Pressure Upstream Throttle Setpoint for Throttled Charged Operation

Table Description – Secondary Pressure Up Throttle setpoint. Set this table to be the same as what you PUT Setpoint table is. This is for normal mode only and the Y axis is MAP Setpoint.

Tuning Tips – None at this time.

Precautions and Warnings – None at this time

Pressure Upstream Throttle Setpoint for Throttled Charged Operation in Sport Mode

Table Description – Secondary Pressure Up Throttle setpoint. Set this table to be the same as what you PUT Setpoint table is. This is for sport mode only and the Y axis is MAP Setpoint.

Tuning Tips – None at this time.

Precautions and Warnings – None at this time

Turbine Setpoint Position for Throttle Mode Turbine Setpoint Position for Throttle Mode Normal Mode

Table Description – Open loop VTG control set point when the car is in normal mode, NOT sport mode.

Tuning Tips – Raise this if you feel the car needs more boost initially.

Precautions and Warnings – None at this time

Turbine Setpoint Position for Throttle Mode Sport Mode

Table Description – Open loop VTG control set point when the car is in sport mode.

Tuning Tips- Raise this if you feel the car needs more boost initially.

Precautions and Warnings – None at this time

Turbine Actuator Position Setpoint – Open Loop Part

Table Description – This table is the open loop control of the boost control system.

Tuning Tips – Raise this value if trying to raise boost pressure.

Precautions and Warnings – None at this time

Folder: Brake Boosting

Brake Torque Limitation

Table Description- Maximum torque table when brake pressure is applied.

Tuning Tips- Raise this value if using brake boosting so that the throttles don't close.

Precautions and Warnings – Use this with caution! It will be temporarily disabling the factory throttle safety control! Make sure the driver knows how to shut down if an error does occur!!!----

Delay Time to Activate Torque Limit

Table Description- Delay time till the throttle limit becomes active.

Tuning Tips- Raise this value if using brake boosting so that the throttles don't close.

Precautions and Warnings – Use this with caution! It will be temporarily disabling the factory throttle safety control! Make sure the driver knows how to shut down if an error does occur!!!

Engine Speed Limit In Case of Throttle Error

Table Description- This is the engine speed limit if a throttle error is present.

Tuning Tips- Raise this value if using brake boosting so that the throttles don't close.

Precautions and Warnings – Use this with caution! It will be temporarily disabling the factory throttle safety control! Make sure the driver knows how to shut down if an error does occur!!!

Minimum Brake Pressure Value for Limit Active

Table Description- This is the minimum brake pedal pressure for the throttle limit to be active.

Tuning Tips- Raise this value if using brake boosting so that the throttles don't close.

Precautions and Warnings – Use this with caution! It will be temporarily disabling the factory throttle safety control! Make sure the driver knows how to shut down if an error does occur!!!

Vehicle Speed Limitation for Brake Limitation

Table Description- Maximum vehicle speed when the brake limitation is active.

Tuning Tips- Raise this value if using brake boosting so that the throttles don't close.

Precautions and Warnings – Use this with caution! It will be temporarily disabling the factory throttle safety control! Make sure the driver knows how to shut down if an error does occur!!!

Folder: Cam Timing

Inlet Camshaft Position Setpoint at High Temperature Level 0-0 thru 3-1

Table Description- Degrees BTDC (before top dead center) that the intake cam opens and closes.

Tuning Tips- Modify this table to try and achieve optimum cylinder filling and to help increase volumetric efficiency. Best modified on a chassis or engine dyno so you can measure results. These are based on varying conditions and in normal mode, NOT sport.Precautions and Warnings – None at this time

Inlet Camshaft Position Setpoint at High Temperature Level for Sport Mode 0-0 thru 3-1

Table Description- Degrees BTDC (before top dead center) that the intake cam opens and closes.

Tuning Tips- Modify this table to try and achieve optimum cylinder filling and to help increase volumetric efficiency. Best modified on a chassis or engine dyno so you can measure results. These are based on varying conditions and in Sport Mode.

Precautions and Warnings – None at this time

Folder: EGT Tables

Setpoint of Turbine Temperature for Overheating Prevention

Table Description- This is an estimated exhaust temp at the turbine. This is a safety to prevent the turbine from getting too hot and causing a possible mechanical failure.

Tuning Tips- You can increase this temp if you are making big power and the exhaust gas temperature appears to be too high. This is a modeled temperature so the actual temperature values can vary. We suggest having a good way to make sure to measure EGT if you are unsure of the actual temperature.Precautions and Warnings – None at this time.

Target Exhaust Gas Temperature for Reference Conditions 1 and 2

Table Description- These tables are exhaust gas temperature targets. Past this the car will try and trim the values back down by implementing methods such as closing throttles.

Tuning Tips- You can increase this temp if you are making big power and the exhaust gas temperature appears to be too high. This is a modeled temperature so the actual temperature values can vary. We suggest having a good way to make sure to measure EGT if you are unsure of the actual temperature.

Precautions and Warnings – None at this time.

Folder: Fuel

Basic Lambda Setpoint 1

Table Description – This is the base lambda table that the car will try and target not under full load, bank 1.

Tuning Tips – Tune this table accordingly for the target lambda values that you would like to achieve.

Precautions and Warnings – None at this time.

Basic Lambda Setpoint 2

Table Description – This is the base lambda table that the car will try and target not under full load, bank 2.

Tuning Tips – Tune this table accordingly for the target lambda values that you would like to achieve.

Precautions and Warnings – None at this time.

Basic Lambda Setpoint Offset Value Basic Lambda Setpoint Offset Value for Knocking Bank 1

Table Description – This is the lambda value that will be removed when knock is detected in bank 1

Tuning Tips – Tune this table accordingly for the amount of fuel you would like added when knock is present in bank 1. The more negative the value the more fuel is injected during knock events.Precautions and Warnings – None at this time.

Basic Lambda Setpoint Offset Value for Knocking Bank 2

Table Description – This is the lambda value that will be removed when knock is detected in bank 2

Tuning Tips – Tune this table accordingly for the amount of fuel you would like added when knock is present in bank 2. The more negative the value the more fuel is injected during knock events.

Precautions and Warnings – None at this time.

Constant for stoichiometric air/fuel ratio (=1/14.7)

Table Description – This value is a ratio based off of the fuel stoichiometry that is being used.

Tuning Tips – The value used should be 1 divided by the stoichiometric air/fuel ratio of the fuel. This may need to be altered when experimenting with alternative fuels.

Precautions and Warnings – None at this time.

Fuel Pressure Setpoint

Table Description – This is the main target fuel pressure table.

Tuning Tips – Use this table for the majority of fuel pressure adjustments. You can increase this table if you are in need of more fuel. You want to data log the set point of fuel pressure with the actual fuel pressure to make sure that you are within an acceptable range. Precautions and Warnings – None at this time. 

Fuel Pressure Target for Double Injection Mode

Table Description – Fuel Pressure target for when the engine is in double or dual injection modes. Dual injection modes generally only occur during the catalytic converter warm up phase and wide open throttle from 2,600RPM to 3,000RPM. During double injection fuel is injected during both the compression and intake strokes.

Tuning Tips – None at this time.

Precautions and Warnings – None at this time.

Fuel Pressure Target for Homogenous Engine Operation

Table Description – Fuel Pressure target while the motor is in Homogenous Engine Operation. Mostly in use during light load operation where stoichiometric AFR is desired.

Tuning Tips – None at this time.

Precautions and Warnings – None at this time.

Lambda Full Load Enrichment

Table Description – This is target fueling for the car when in full load, or wide open throttle. These are the target value that the car will try and achieve based on an amount of time in full load. This table is used when NOT in Sport Mode.

Tuning Tips – Set these tables according to what lambda you want to run. We recommend around a .8 lambda at full load. You can also log the full load flag in the software to know when the car is going to full load mode. These tables are on a timer.Precautions and Warnings – None at this time.

Lambda Full Load Enrichment for Sport Mode

Table Description – This is target fueling for the car when in full load, or wide open throttle. These are the target value that the car will try and achieve based on an amount of time in full load. This table is used when IN Sport Mode.

Tuning Tips – Set these tables according to what lambda you want to run. We recommend around a .8 lambda at full load. You can also log the full load flag in the software to know when the car is going to full load mode. There tables are on a timer.

Precautions and Warnings – None at this time.

Map Map for the Low Pressure Fuel Pump Duty Cycle Pump 1 & 2

Table Description – This table helps to control the electric fuel pump, based on fuel flow. This can be changed to help aid in fuel delivery.

Tuning Tips – If you notice a drop in fuel pressure attempt to raise the duty cycle for the low pressure pumps.Precautions and Warnings – None at this time.

Minimum Lambda Value for Turbocharger Overheating Protection

Table Description – Lowest lambda the car will target if turbo protection is active.

Tuning Tips – Monitor turbo protection to see if protection mode is engaged.

Precautions and Warnings – None at this time.

Start of Injection Map (Warm)

Table Description – This is the map that will help to control the start of injection timing when the car is warmed up. Use this map to change start of injection timing to help with overall fueling efficiency by helping to dictate when the injector is starting to fire based on crank angle. This can help to reduce emissions, pick up power and increase fuel efficiency.

Tuning Tips – None at this time.

Precautions and Warnings – None at this time.

Stoichiometric Fuel Constant: 14.7

Table Description – This is the stoichiometric target for the ECU, on gasoline.

Tuning Tips – Change this if you want to change fuels that have a different lambda value. Do this at your own risk!Precautions and Warnings – None at this time.

Folder: Ignition Timing

Absolute Calibration for Reference Ignition Angle Due to Valve Overlap 0-0 thru 1-3

Table Description – These tables are ideal timing numbers to achieve overall efficiency, or MBT timing.

Tuning Tips – There should be no need to make changes to these tables, as they are already high enough. If you want to make changes to ignition timing it should be done in the Calibration for Reference tables.

Precautions and Warnings – None at this time.

Basic Minimum Ignition Angle 0-0 thru 1-1

Table Description – These 4 tables are the timing floor for varying conditions. This is the least amount of ignition timing the car can run.Tuning Tips – None at this time.

Precautions and Warnings – None at this time.

Calibration for Reference Ignition Angle Due to Valve Overlap 0-0 thru 1-3

Table Description – These are the main ignition timing maps. These are the maps that you will need to modify in order to make changes to the ignition timing. These are base calibration numbers for the ignition timing, before any corrections will be applied based on load.

Tuning Tips – You want to make sure that you are making changes to the all the timing maps to be sure that the car is tuned at all load sections, as it will move between the maps on varying conditions.

Precautions and Warnings – None at this time.

Ignition Angle Correction for Turbocharger

Table Description – This is an ignition timing correction based on turbo boost pressure. The car will pull timing through most of peak boost to help and maintain safe cylinder pressures.

Tuning Tips – Make changes to this if you want there to be less timing pulled at peak boost, or if you just want to have a bit more control over overall ignition timing and don't want this to be an ancillary system to pull timing.

Precautions and Warnings – Removing this or setting this table to 0 is going to make the car increase ignition timing by a good amount. This can and will increase cylinder pressures so be sure to datalog to make sure the car is in good running order.

Folder: Knock Control

Knock Retard Threshold Per Knock Event

Table Description – The amount of timing retard in degrees that gets pulled during each knock event.

Tuning Tips – Change this if you feel that the car is pulling too much timing or too little timing depending on the knock event. USE THIS WITH GREAT CAUTION!

Precautions and Warnings – None at this time.

Knock Threshold Cylinder 1-6

Table Description – These thresholds are made to determine when the knock control system becomes active. Raising these thresholds will make the car less likely to pull timing when it hears something it deems as a knock event. Use this on built motors when the harmonics of the engine can change the amount of noise the knock sensor deems as knock, when in fact, it is just engine noise. The numbers are for each individual cylinder.

Tuning Tips – None at this time.

Precautions and Warnings – None at this time.

FolderFolder: Launch Control

Duration of Single Cylinder Cut for Race Start

Table Description- The amount of time each cylinder is cut when on launch control. This a per cylinder time.

Tuning Tips- Raise this if you feel that the cylinder cut should be longer.

Precautions and Warnings – This will raise the EGT's and can cause damage to the engine and turbo! Use with CAUTION!

Duration of the Combustion (non-SCC) Phase at "Hard" Mode of Engine Speed for Race Start

Table Description- Time durations for the launch control mode to be active.

Tuning Tips- None at this time.

Precautions and Warnings – None at this time.

Engine Overspeed Threshold for Disabling the Engine Speed Limit Controller at Race Start

Table Description- Above this limit when in race start the car will use the launch control limiter for the race start, or launch control, command.

Tuning Tips- None at this time.

Precautions and Warnings – None at this time.

Map for Torque Reserve for Engine Speed Limitation Output by 'Race Start'

Table Description- This table is an increase at race start in torque output. It will help to make boost at the start line.Tuning Tips- None at this time.

Precautions and Warnings – None at this time.

Passive Value of Torque Reserve for Engine Speed Limitation by 'Race Start'

Table Description- This is a torque increase value for the launch control function. Raising this value will allow you to yield a higher launch control power request.

Tuning Tips- In order to use this you will also want to make sure that the Pre-Throttle Target Pressure for Race Start is also raised accordingly so that when increasing it, the two tables are not fighting each other.

Precautions and Warnings – None at this time.

Pre-Throttle Target Pressure for Race Start

Table Description- Target boost pressure for launch control. This is the actual target that will be targeted when on launch control.

Tuning Tips- Raise this or lower it to make the launch more or less aggressive.

Precautions and Warnings – None at this time.

Folder: Limits

Dynamic (Increased) Engine Speed Limit for High Range

Table Description- Engine speed limiter.

Tuning Tips- None at this time.

Precautions and Warnings – None at this time.

Dynamic (Dynamic (Increased) Engine Speed Limit for Low Range

Table Description- Engine speed limiter.Tuning Tips- None at this time.

Precautions and Warnings – None at this time.

Engine Coolant Threshold to Decrease Engine Power

Table Description- Maximum engine coolant temp before the ECU will limit power. Above this temperature the ECU will dial back power.

Tuning Tips- None at this time.

Precautions and Warnings – None at this time.

Static (Standard) Engine Speed Limit for High Range

Table Description- Engine speed limiter.

Tuning Tips- None at this time.

Precautions and Warnings – None at this time.

Static (Standard) Engine Speed Limit for Low Range

Table Description- Engine speed limiter.Tuning Tips- None at this time.

Precautions and Warnings – None at this time.

Threshold to Vehicle Speed Limitation

Table Description- Vehicle speed limiter.

Tuning Tips- None at this time.

Precautions and Warnings – None at this time.

Folder: Miscellaneous

Engine Displacement

Table Description- Displacement of the engine in liters.

Tuning Tips- Change this value only if the displacement of the engine changes, as this is used in the mass flow calculation by the ECU.Precautions and Warnings – None at this time.

Folder: Sensor Calibration

Conversion Table for MAF Value

Table Description – This table is the offset to convert the raw value into the calculated value for the MAF readings.

Tuning Tips – None at this time.

Precautions and Warnings – None at this time.

MAP Sensor Linear Voltage Scaling

Table Description – This is the scaling value for the MAP sensor. Stock the MAP sensor is a 3 bar sensor.

Tuning Tips – This is a linear scale. If you have questions on how to scale this please contact the Porsche Experts. 

Precautions and Warnings – None at this time.

Maximum MAP Sensor Voltage for Error

Table Description – This is the maximum voltage that the ECU can see from the MAP sensor before it throws a P1183 or P1184. These are basically overboost faults and get triggered from the voltage being too high from the MAP sensor.

Tuning Tips – Raise this value to 5 volts to ensure that you are using the full range of the sensor installed.Precautions and Warnings – None at this time.

Maximum PUT Sensor Voltage for Error

Table Description – This is the maximum voltage that the ECU can see from the PUT sensor before it throws a P1639 or P1638. These are basically overboost faults and get triggered from the voltage being too high from the PUT sensor.

Tuning Tips – Raise this value to 5 volts to ensure that you are using the full range of the sensor installed.

Precautions and Warnings – None at this time.

Minimum MAP Sensor Voltage for Error

Table Description – This is the minimum voltage that the ECU can see from the MAP sensor before it throws a plausibility error.

Tuning Tips – There shouldn't be any reason to change this value unless you are using a map sensor that needs to get scaled under this value.

Precautions and Warnings – None at this time.

Minimum PUT Sensor Voltage for Error

Table Description – This is the minimum voltage that the ECU can see from the PUT sensor before it throws a plausibility error.

Tuning Tips – There shouldn't be any reason to change this value unless you are using a map sensor that needs to get scaled under this value.Precautions and Warnings – None at this time.

PUT Sensor Linear Voltage Scaling 

Table Description – This is the scaling value for the PUT sensor (pressure sensor upstream of the throttle in the charge piping). Stock the PUT sensor is a 3 bar sensor.

Tuning Tips – None at this time.

Precautions and Warnings – None at this time.

Folder: Throttle

Driver Interpretation Map for High Vehicle Speeds

Table Description- This table is a percentage of torque applied based on pedal position. This is for normal driving mode, non-sport mode. This is for high vehicle speeds which is ABOVE 70 km/h (44MPH)

Tuning Tips- Raising this table will make the pedal percentage more aggressive. It can be used to make the car feel more responsive. This table is for normal mode, NOT for Sport Mode.

Precautions and Warnings – None at this time.

Driver Interpretation Map for High Vehicle Speeds in Sport Mode

Table Description- This table is a percentage of torque applied based on pedal position. This is for sport mode. This is for high vehicle speeds which is ABOVE 70 km/h (44MPH)

Tuning Tips- Raising this table will make the pedal percentage more aggressive. It can be used to make the car feel more responsive. This table is for Sport Mode.Precautions and Warnings – None at this timefor Sport Mode.

Driver Interpretation Map for Low Vehicle Speeds

Table Description- This table is a percentage of torque applied based on pedal position. This is for normal driving mode, non-sport mode. This is for high vehicle speeds which is BELOW 70 km/h (44MPH)

Tuning Tips- Raising this table will make the pedal percentage more aggressive. It can be used to make the car feel more responsive. This table is for normal mode, NOT for Sport Mode.Precautions and Warnings – None at this time.

Driver Interpretation Map for Low Vehicle Speeds in Sport Mode

Table Description- This table is a percentage of torque applied based on pedal position. This is for sport mode. This is for high vehicle speeds which is BELOW 70 km/h (44MPH)

Tuning Tips- Raising this table will make the pedal percentage more aggressive. It can be used to make the car feel more responsive. This table is for Sport Mode.

Precautions and Warnings – None at this time.

Driver Interpretation Map for High Vehicle Speeds in Sport Plus Mode

Table Description- This table is a percentage of torque applied based on pedal position. This is for sport plus mode. This is for high vehicle speeds which is ABOVE 70 km/h (44MPH)

Tuning Tips- Raising this table will make the pedal percentage more aggressive. It can be used to make the car feel more responsive. This table is for Sport Plus Mode.

Precautions and Warnings – None at this time.

Driver Interpretation Map for Low Vehicle Speeds in Sport Plus Mode

Table Description- This table is a percentage of torque applied based on pedal position. This is for sport plus mode. This is for high vehicle speeds which is BELOW 70 km/h (44MPH)

Tuning Tips- Raising this table will make the pedal percentage more aggressive. It can be used to make the car feel more responsive. This table is for Sport Plus Mode.

Precautions and Warnings – None at this time.

Maximum Throttle Position in Optimum Response Mode

Table Description- Maximum throttle value possible when the ecu is in Optimum Response mode.

Tuning Tips- Raise this so that the maximum possible throttle position is higher in Optimum Response mode.Precautions and Warnings – None at this time.

Pedal Value Threshold for Disabling Torque Limitation

Table Description- Threshold value in pedal position that will disable the torque limit above the set value.Tuning Tips- None at this time.

Precautions and Warnings – None at this time.

Upper Limit of the Throttle Position Setpoint

Table Description- Maximum value the throttle plate is allowed to open.

Tuning Tips- None at this time.

Precautions and Warnings – None at this time.

Toggles (Base)