GT-R E-Tune R35 

A Brewed Pro tune or E-tune ensures your engine is running at peak efficiency making reliable power based on your exact GTR build. Engine mods, fuel grade and elevation all play major rolls in how an engine runs, there is no better way to ensure your engine is getting exactly what needs than a custom E-tune. Whether you have a stock VR38dett with bolt on parts or a fully built GTR running staged injection and Ethanol fuel we are here to support with tuning and data analysis every step of the way. From the first engine start to the each pass down the drag strip we analyze all the data in order to perfect each tune on every GTR we work with.

Re-tune and upgraded tune packages: If you purchase a “Bolt on Mods” tune package and then decide to upgrade to a higher level tuning package you can do so at any time and we will apply your original tuning package as a credit towards your upgrade. This saves you time and money making a retune for your R35 cost effective and fast.

E-tuning works as follows:

1. Brewed Motors makes a custom base calibration “Map” for your Cobb AccessPort based on your exact engine mods and emails it to you.
2. You upload the calibration to your AP/car.
3. You take the requested Data logs Brewed Motors can walk you through this step and will also tell you exactly what parameters to log and how to drive IE: RPM and Throttle position **you will need to use a nice straight, flat road/surface you can safely do 3rd gear pulls on.**
4. Email Brewed Motors your Data Logs
5. Brewed revises the calibration based on your data log and emails the new calibration. You can normally expect your updated calibration within 24 business hours however it may take 48 hours during race season. 
6. “Re-Tune” after new parts are installed or new fuel type is used we normally charge $100  for a re-tune unless there has been very drastic change in the engine/setup. Even if big changes are made we will always be able to give a special re-tune price to returning customers, just send us an email or give us a call!

Pre Tuning Preparation:

1. Boost leak test the car. (This ensures there are no leaks, even a small leak will have a big effect on the tune and cause problems down the road.) Click here to check out a great DIY boost leak tester article and build instructions from a Subaru guy.
2. Test for coolant, oil and fuel leaks (because fires are BAD).
3. Spark plugs; check you are using the correct heat range plug and that the plug is gapped correctly
4. Check your wide band AFR O2 sensor is working correctly and connected to the EMS/ECU and or data logger
5. Ignition sync; on most engine you should use a timing light to check that ignition timing at the engine matches the ignition timing value at the EMS/ECU ​

Commonly used/requested data logs:

***Note*** Each data log should be kept as short as possible (10-20 seconds is normal) Logs should be done in 3rd gear unless otherwise stated. DO NOT do any High throttle pulls or data logs until we have finished tuning the low/mid range throttle ranges.​

1. Engine start (cold start/engine warm up) this log will be one of the longest logs (logging from cold start to operating temperature).
2. Engine start/idle (warm/operating temp) this log is normally ~15 seconds
3. Low throttle (~10% throttle from idle to 4000 rpm) **holding throttle steady is the most important factor here, do not change the throttle position during the log.**
4. Low throttle (~20% throttle from idle to 4000 rpm)**holding throttle steady is the most important factor here, do not change the throttle position during the log.**
5. Mid throttle (~40% throttle from idle to 5000 rpm)**holding throttle steady is the most important factor here, do not change the throttle position during the log.**
6. High throttle (~60% throttle from idle to redline)**holding throttle steady is the most important factor here, do not change the throttle position during the log.**
7. High throttle (100% throttle from idle to redline)**holding throttle steady is the most important factor here, do not change the throttle position during the log.**​

GT-R R35 Data Logging Parameters/Monitors

• Bolded Monitors indicate recommended data log parameter for Accessport E-tune.

Units: (standard, metric)

1. A/C System Pressure – (MPa) A/C system pressure.
2. A/F ALPHA (Avg. Learning) B1 – (%) – Average learned fuel correction bank 1.
3. A/F ALPHA (Avg. Learning) B2 – (%) – Average learned fuel correction bank 2.
4. A/F Ratio B1 – (AFR, Lambda) – Internal wide-band oxygen sensor bank 1. Actual AFR/Lambda reported by the ECU.
5. A/F Ratio B2 – (AFR, Lambda) – Internal wide-band oxygen sensor bank 2. Actual AFR/Lambda reported by the ECU.
6. Air Fuel B1 CMD – AFR/Lambda final request before compensations.
7. Air Fuel B2 CMD – AFR/Lambda final request before compensations.
8. Active Map Slot – (#) -Real time switchable map currently in use by the ECU (0-8)
9. Accelerator pedal Pos. – (%) Input from the driver.
10. Accelerator pedal Pos. Hijack – (%) Debug monitor for engine safety and rolling boost system. This is used to verify the throttle request during an engine safety event or rolling boost.
11. Barometric Pressure – A measure of atmospheric pressure
12. Battery Voltage – (V)
13. Clutch Torque – (nm, ft/lbs) – Output value from the clutch torque table, sent to the transmission control unit and affects clutch lock-up.
14. Coolant Temp – (deg. F, deg. C) – Engine coolant temperature.
15. Differential Fuel Pressure – (psig) – Fuel pressure minus manifold relative pressure (sea level), this is the effective pressure used for injector flow determination.
16. Differential Fuel Pressure Compensation – (%) – The amount of compensation applied by the differential fuel pressure compensation table.
17. Differential Fuel Pressure Error (PSI) – (psi error) – The amount of differential fuel pressure error in PSI as referenced against the base fuel pressure table.
18. Differential Fuel Pressure Error (Percent) – (% error) – The amount of differential fuel pressure error in % as referenced against the base fuel pressure table.
19. Dynamic Advance (DBA) – ( deg.) – monitor used for DBA ignition timing only. Degrees of advance added or subtracted due to current engine noise or detonation
20. End of injection Timing – (deg.) – Timing for end on injection in rotational degrees after top dead center.
21. Engine Oil Temp. – (Deg. F, Deg. C) – Engine oil temperature.
22. Engine Speed – (RPM) – Engine speed in revolutions per minute.
23. Ethanol % – (%) – Custom monitor for COBB Flex fuel. Reports ethanol content when fitted with appropriate hardware and enabled in map.
24. Enabled BOTL – (0-1) Custom monitor for COBB Boost off the line. When enabled this monitor will display a value of 1. If the system is not engaged it will display a value of 0.
25. Enabled ROLL – (0-1) Custom monitor for COBB Rolling Boost. When enabled and active this monitor will display a value of 1. If the system is not engaged it will display a value of 0.
26. Enabled SAFETY – (0-1) Custom monitor for COBB Engine Safety. When active (an active fault/failure state) this monitor will display a value of 1. If the system is not engaged it will display a value of 0.
27. Fuel Temp – (Deg. F, Deg. C) in tank Fuel Temperature.
28. Fuel Cut Flags – (raw) – These values represent any active cylinder fuel cuts. In the case of multiple simultaneous injection cuts, the values get added together.
29. Fuel Pressure – (P.S.I., k.P.a.) Custom monitor for COBB Engine Safety/Fuel pressure. If an external senor is equipped, activated and calibrated, this will display current fuel pressure.
30. Fuel Pump (Sub) Status – (0-1) – The current active status of the oem secondary fuel pump.
31. Fuel Temperature Compensation – (%) – The amount of compensation applied by the fuel temperature compensation table.
32. Gear – Current active gear.
33. High Det. Flag (ON/OFF) – monitor that reports normal low detonation (0) or high detonation (1) conditions. Requires key cycle event to clear out high det. mode events.
34. Idle Speed Target – (RPM) Target idle speed
35. Ignition Timing – (deg.) – Ignition timing in degrees before top dead center. This is the final commanded ignition timing after all correction and adjustments.
36. Inj. Duty Cycle – (%) – Total injector pulse width as a percentage of available injector open time. If staged injection is active, this value will indicate the duty cycle the primary injectors would be at if the secondary injectors were not active.
37. Inj. Duty Cycle (Staged) – (%) – Total injector pulse width as a percentage of available injector open time. If staged injection is active, this value will indicate the current duty cycle that both the primary and secondary injectors are operating at.
38. Inj. Pulse Width Cyl 1-6 – (ms) – Total open time of fuel injector.
39. Inj. Pulse Width Cyl. 1-6 (Effective) – (ms) – Total injector open time minus latency, this is the effective time the injector is actually flowing fuel.
40. Inj. Pulse Width 1-6 Final (Post Compensation) – (ms) Final Inj. pulse width after all compensations. 
41. Inj. Pulsewidth Latency – (ms) – The current injector latency as calculated from the oem multiplier/offset tables or from the 3D Latency table when enabled.
42. Intake Air Temp. – (deg. F, deg. C) – Sensor value intake air temperature.
43. Intake Valve Timing (B1 and B2) – (deg.) – Position in degrees of variable intake camshaft.
44. ISC Accessory Load Airflow Compensation – (L/min) Additional airflow added to base airflow based off of power steering, A/C, and alternator loads. 
45. ISC Airflow Learning – (L/min) ISC airflow long term learned value. This value is initialized after reset to the value stored to eprom during a bank airflow learning procedure.
46. ISC A/C Airflow Compensation – (L/min) Additional airflow added to base airflow when A/C compressor is active. 
47. ISC Base Airflow – (L/min) Current base airflow calculation based on target idle speed. 
48. ISC Dashpot Airflow Compensation – (L/min) Additional airflow compensation applied immediately upon entering idle mode and decayed by dashpot airflow decay rate value. 
49. ISC Final Airflow – (L/min) Final idle speed control airflow request. 
50. ISC Integral Feedback Airflow – (L/min) Integral feedback airflow compensation. This is the primary feedback for idle airflow control. 
51. ISC Opening Area – (cm²) Calculated opening area based on ISC final airflow. This value will be added to requested opening area from requested torque. 
52. ISC Power Steering Airflow Compensation – (L/min) Additional airflow added to base airflow proportional to power steering sensor voltage. 
53. ISC Proportional Feedback Airflow – (L/min) Proportional feedback airflow compensation. This is only active when below idle speed target. 
54. Knock Cy 1-6 – (raw) – raw knock value from each cylinder
55. Knock Filter 1-6 – (raw) – knock sensitivity threshold level for each cylinder
56. Knock Sums (CBA) – (raw) – A monitor that reports active ignition timing adjustment in response to engine noise – an increment of 300 is equivalent to 1 degree of ignition removed. Used ONLY in CBA ignition strategy cars
57. Launch Control Fuel Compensation – (%) – The amount of fueling compensation applied by the launch control fuel compensation table while in launch mode.  
58. Launch Control RPM Error – (RPM) – The amount of launch control engine speed target error.
59. Launch Control Status – (0-1) – The current active status of the launch control system.
60. Limp Status (Safety) – Custom monitor for COBB Engine Safety. This is currently a compound monitor, allowing you to see all failure state causes in a single monitor.
61. LTFT (KBLRC) B1 – (%) – Long-Term Fuel Trim Bank 1. This long-term fuel trim indicates an average learned fuel correction needed to maintain the closed loop target for Bank 1.
62. LTFT (KBLRC) B2 – (%) – Long-Term Fuel Trim Bank 2. This long-term fuel trim indicates an average learned fuel correction needed to maintain the closed loop target for Bank 2.
63. MAF Bank 1 – Mass air flow sensor output in g/s for Bank 1.
64. MAF Bank 2 – Mass air flow sensor output in g/s for Bank 2.
65. MAF Total – Total airflow in grams per second for bank A and B (A+B/2)
66. MAF V Bank 1 – (V) – Mass air flow sensor output voltage for Bank 1.
67. MAF V Bank 2 – (V) – Mass air flow sensor output voltage for Bank 2.
68. MAP – (PSI, kPa) -Manifold Absolute Pressure (reported as negative values in vacuum and positive values in boost) – logged from pressure sensor in the intake manifold.
69. MAP Driver Pre Voltage – (V) – Voltage reading for the pre-throttle body boost pressure sensor. Alternately, shows the voltage reading for fuel pressure sensor if vehicle is outfitted with aftermarket fuel pressure sensor (Used for fuel pressure sensor debugging) – logged from the driver’s side (left) pre-throttle body pressure sensor. Use “Turbo Boost Pressure Left” for sensor pressure readings.
70. MAP Pass Pre Voltage  – (V) – Voltage reading for the pre-throttle body boost pressure sensor. Alternately, shows the voltage reading for fuel pressure sensor if vehicle is outfitted with aftermarket fuel pressure sensor (Used for fuel pressure sensor debugging) – logged from the passenger side (right) pre-throttle body pressure sensor. Use “Turbo Boost Pressure Right” for sensor pressure readings.
71. Max negative dynamic advance (DBA) – (deg.) – largest negative DA currently recorded in ECU memory
72. Non Linear Pulsewidth Compensation – (%) – The amount of compensation applied by the non-linear pulsewidth compensation table.
73. Per Cylinder Injector 1-6 Compensation – (%) – The amount of compensation applied by the corresponding per cylinder injector compensation table.
74. Power Steering Pressure Sensor Volts – (V) Voltage reported from power steering pressure sensor. 
75. STFT (ALPHA) B1 – (%) – Active short-term fuel trim for bank 1 needed for the ECU to meet fuel targets in fuel table A.
76. STFT (ALPHA) B2 – (%) – Active short-term fuel trim for bank 2 needed for the ECU to meet fuel targets in fuel table A.
77. Staged Injection Airmass Ratio – (%) – Percentage of airmass being combusted by fuel injected from the secondary injectors.
78. Staged Injection Corrected Lambda – (AFR/Lambda) – When multi-fuel is enabled, this value will represent the final closed loop target lambda based on standard commanded lambda and staged injection secondary commanded lambda.
79. Staged Injection Cycle Counter – (Engine Cycles) – Number of engine cycles that have taken place since the staged injection system has activated or deactivated.
80. Staged Injection Secondaries Active Status – (0-1) – Current active status of the secondary injectors.
81. Staged Injection Secondary Injection Latency – (ms) – The current secondary injector latency as calculated from the Secondary Injector Latency table.
82. Staged Injection Secondary Lambda – (AFR/Lambda) – When multi-fuel is enabled, this represents the commanded lambda used by the secondary injector fueling calculations as looked up in the Secondary Fuel Commanded Lambda (Multi-Fuel) table.
83. Staged Injection Staged Pulsewidth – (ms) – Injector pulsewidth as it would be when secondary injectors are active, this value is calculated whether secondary injection is active or not.
84. Staged Injection Threshold Flags – (raw) – Current status of all staged injection activation thresholds, when multiple thresholds have been exceeded their values are added together.
85. Staged Injection Transition Compensation – (%) – Fuel compensation currently being applied by the staged injection transition compensation system, this value is pulled from either the Transition Compensation (Staging) or (De-staging) table.
86. Start of injection Timing – (deg. ) – Timing for end on injection in rotational degrees after top dead center.
87. Theoretical Pulse Width – (ms) – Load calculation based upon theoretical injector open time. This is used as load axis scaling for several critical tables throughout the ECU.
88. Throttle Angle B1 (Actual) – (deg.) Degrees of opening angle for bank 1 throttle body. 
89. Throttle Angle B1 (Target) – (deg.) Degrees of opening angle targeted for bank 1 throttle body. 
90. Throttle Angle B2 (Actual) – (deg.) Degrees of opening angle for bank 2 throttle body. 
91. Throttle Angle B2 (Target) – (deg.) Degrees of opening angle targeted for bank 2 throttle body. 
92. Throttle Opening Airflow Factor – (Factor) – Value used as an x-axis lookup for the wall film adhesion factor table.
93. Throttle Opening Area – (cm2) – Opening area per throttle body, includes requested torque opening area added to idle speed control opening area.
94. Throttle Position B1  – (%) – throttle plate opening 0 to 100%
95. Throttle Position and B2 – (%) – throttle plate opening 0 to 100%
96. TPS Volts B1 (Main Sensor) – (V) Throttle position sensor voltage Bank 1 (main sensor)
97. TPS Volts B1 (Sub. Sensor) – (V) Throttle position sensor voltage Bank 1 (main sensor error checking)
98. TPS Volts B2 (Main Sensor) – (V) Throttle position sensor voltage Bank 2 (main sensor)
99. TPS Volts B2 (Sub. Sensor) – (V) Throttle position sensor voltage Bank 2 (main sensor error checking)
100. Trans. Req Tq1 – (raw)
101. Trans. Req. Tq2 – (raw)
102. Turbo Boost Pressure Left – (PSI, kPa) – Boost pressure on left side of motor – sensor located in front of left throttle body.
103. Turbo Boost Pressure Right – (PSI, kPa) – Boost pressure on right side of motor – sensor located in front of right throttle body.
104. Vehicle speed – (mph, kph) – Speed calculated by vehicle speed sensor.
105. Wall Film Adhesion Factor – (Factor) – Final wall film adhesion factor value after being compensated by the wall film adhesion compensation (RPM) table output.
106. Wastegate Duty – (%) – Percentage of boost control wastegate solenoid duty cycle % (0 to 100).
107. Wheel Speed (FL, FR, RL, RR) – (MPH, KPH) Individual wheel speeds. (Front Left, Front Right, Right Left, Right Rear)

**All Tuning and Etune services are intended for off road Motorsports use only. Please respect the environment and do not remove emissions equipment from vehicles used on public roads. We also offer a range of Gesi high flow cat equipped down pipes WITH EPA approval to keep your car emissions compliant.