Map Changes
Boost Control
Using RaceROMs updated boost control strategy the boost target was raised from 2.0bar (Absolute) to 2.25bar peak and held much higher at higher RPM. there is a map per mode all set the same, however they can be adjusted to suit your customer if required.
The Boost target max allowed #1 and and Boost Controller Maximum was also increased to accommodate the higher boost target
Wastegate Control
The VR30TT has electronic waste-gates that use a 0-8mm position setting as opposed to 0-100% duty cycle, they function in the same way but have much greater accuracy and have the ability to be fully open with manifold vacuum. To achieve the increased boost targets the WG base target position (and corresponding EGR OFF table) and Boost Correction Integral Multiplier were adjusted.
Infiniti Q50 VR30TT example ROM
As part of the VR30TT series development EcuTek has developed an example ROM for the EU Q50RS. Testing has revealed the best methods to achieve reasonable gains without large risks. The end result of our testing was the creation of a series of Example ROMs that would give the tuner the basic modifications to the ROM that increase horsepower and remove the limits. This Q50RS ROM file (6HF2D-34204-exampleROM-enc.bin) should be used as a guide to tune from and any "self tunes" should be based on this ROM.
Results and Map Changes
The example ROM with a scorpion exhaust gained 100lbs.ft torque and roughly 60hp at the flywheel (453hp 470lbs.ft) over the stock calibration (410hp 375lbs.ft). It uses a combination of increase boost, turbo speed, WG and VVT angle on top of changed fuel and ignition targets to achieve the increase.
Stock Vs tuned with exhaust
The list of maps changes is relatively low to achieve such a gain, below is a ROM compare of a stock and tuned ROM.
Rom Compare Map listing
Map Changes
Boost Control
Using RaceROMs updated boost control strategy the boost target was raised from 2.0bar (Absolute) to 2.25bar peak and held much higher at higher RPM. there is a map per mode all set the same, however they can be adjusted to suit your customer if required.
TheBoost target max allowed #1and andBoost Controller Maximum was also increased to accommodate the higher boost target
Wastegate Control
The VR30TT has electronic waste-gates that use a 0-8mm position setting as opposed to 0-100% duty cycle, they function in the same way but have much greater accuracy and have the ability to be fully open with manifold vacuum. To achieve the increased boost targets theWG base target position (and corresponding EGR OFF table) andBoost Correction Integral Multiplierwere adjusted.
The Boost Correction - Air Temp MultiplierandWastegate Correction - Manifold Absolute Pressureboth have axis adjustments carried through from other maps.
Turbo Speed limits also need to be raised to allow the boost target to be made. TheWastegate Correction - Turbo Speed Threshold has been increased to 245kRPM, the increase in speed can affect reliability so increase with caution and understanding.
Fuelling
Fuel targets have been set for each mode, there is an increase in the axis and then set a little richer at these higher load points.
The Fuel Map - Safe Mode also has the axis adjusted for higher load.
Ignition Timing
The ignition timing load axis and output values have been increased in the higher load regions to give the extra torque and power.
All Map switch modes have been set the same but the safe mode has been modified to better suit the potential loads and retarded to give improved safety.
The ignition timing Max maps also have the load scale increased and the timing values at higher RPM and load to allow the timing to be increased in the absence of knock.
The Ignition Timing Retard Limit and Knock Sensitivity maps share an axis with the ignition timing maps but the output values do not need adjusting.
Variable Valve Timing
There are many VVT maps in the infiniti calibration used for many different modes, in the example ROM the intake cam advance has been increased to optimise performance. the changes have only been made at high QH0 (relative throttle opening).
All of the maps have been adjusted in the same amount even though Map #9 is used in nearly all conditions.
The example ROM is available in your C:\EcuTek\ProECURomFiles\Nissan\VR30TT\Example ROMs folder and should be used a guide; we recommend testing any map changes before releasing the car. Hopefully this is enough information to set you up for the same gains that we made on our Q50RS, further tweaking and adjustment can be made to push more power out from this incredible platform.
