ECU Computer Custom Tune for V8 Holden & HSV Models VT2, VU, VX, VY, VZ

The Standard Computer Settings running your VT to VZ Commodore V8 Engine are pre-set from the factory to meet a variety of parameters such as emissions and all weather conditions etc at a cost of Power & Torque.

The MAF (Air Flow Meter) combined with the MAP Sensor is used along with a long equation to calculate air density and volume which is used by all aspects of the tune calculation. Speed Density (MAFLESS) removes the airflow meter and soley uses the MAP Sensor for this calculation. They both get tuned independently from each other in the standard GM Holden settings and combined together at the end to improve part throttle driveability/mpg, etc. 

By Custom Tuning the ECU to exact suit your cars Engine and Bolt on Parts/Modifications there are good gains to be had on any standard factory tune that will change the way the car behaves/drives as well as improvements in fuel economy.

Even adding just the XAIR OTR Intake on some models we’ve found this can exceed the factory Torque Management settings. If you feel the car hesitate slightly during full throttle acceleration then your car is probably making too much power for the standard settings. The Auto Trans line pressure on all VT to VZ Models is also calculated from torque so if you add an intake or headers and exhaust etc, basically anything that increases the torque will effect the line pressure calculation hence can cause premature wear on any VT-VZ trans if a custom tune is not done to suit.

So to make the most out of the OTR or any other mods a full MAF or MAFLESS Custom Dyno Tune from us or one of our authorised Tuner/Dealers is recommended. Expect much improved throttle response, an additional 15-20kw power gain, more torque plus even better fuel economy over just bolting on the XAIR OTRCAI. The modifiedTrans settings improve the speed of gear changes plus moving shift points in Power Mode creating a much nicer drive.

Why are cars tuned MAFLESS?

When you put a lot more Air in via the XAIR OTR Cold Air Intake there is still a restriction point where the Air runs through the MAF. This is especially the case on VT, VU, VX & VY Models as the MAF only has a 70mm Diameter opening plus thick honeycomb insert which further blocks airflow. For this reason there are big gains, in some cases 10kw at the rear wheels (13kw at the Engine) to be had by tuning the car to run without the Air Flow Meter (MAFLESS) vrs tuning with the MAF In place. Even more when combined with other modifications such as Headers and Big Bore Free Flow Exhaust. MAFLESS the computer uses the MAP Sensor in conjunction with IAT (Air Temp) sensor but with no restriction from the small MAF/honeycomb. On MAFLESS the tuning software circumvents the limitations of the LS1's older MAF and slower PCM. In stock form your ECU has trouble implementing fueling transitions as per MAF calcs due to its slower speed, MAFLESS uses Volumetic Efficiency lookups to derive fuel calculations at part throttle conditions. Further tuning the Volumetric Efficiency improves driveability and fuel economy. VT2, VU, VX & VY Models all feature a separate Air Temp Sensor which makes going to MAFLESS very easy. The Air Temp Sensor is plugged directly into the grommet in the pre-drilled hole in the XAIR OTR Intake Body and longer MAFLESS Hose is used to join the Intake Neck directly to the Throttle Body. VT2, VX & VY 300kw HSV GTS with 5.7 C4B Engine were tuned MAFLESS from the factory.

VZ Models feature the newer style larger MAF without so much restriction so there's generally only a 5-6kw (7-8kw at the Engine) difference between MAFLESS and MAF In Tuning with Bolt on mods such as Intake, Headers & Exhaust. The VZ MAF incorporates the Air Temp Sensor function so a Separate Air Temp Sensor is required to go MAFLESS. If you're on a budget Tuning your VZ with the MAF In is worthwhile however If you have done Headers/Exhaust and want the most power/performance possible then purchase the VZ Separate Air Temp Sensor with Plug in Loom and get the car tuned MAFLESS. 

MAFLESS Tuning is also preferred for all VT to VZ Models when tuning high performance engines with Aftermarket Camshafts or Forced Induction. These MAFLESS Tunes take a lot longer to do to as Idle and Cold Start settings need to be custom set to suit. 

Note : A Mafless tune uses an exact pre-programmed fuel table that does not compensate for Intake or Exhaust changes therefore requires retuning anytime further changes are made to the Engine.

Why are HSV's so much more powerful from the Factory with the same Engine?

All V8 VT2, VX & VY HSV's have Factory Headers and a better ECU Tune from the factory to suit which is why they're generally 30kw more than the equivalent model Holden. VZ HSV has the even larger 6.0 LS2 297kw Factory Engine. These HSV's will not make the same type of Power gains over factory as the lesser tuned Holden V8's. (See Power Upgrades section which shows gains with individual modifications for each car model).

If you are not close to one of our authorised Tuners/Dealers we have Tunes on file from hundreds of other Cars previously done with various modifications. Simply email us your car make/model and year along with a list of modifications/bolt on parts including product brands. We will then email you back confirming we have a tune available to suit your car and its modifiactions.. Courier your Car ECU to us and we will Flash the best Tune into your ECU relevant to your modifications and courier back to you. While not as good as a full custom Dyno Tune a Flash Tune is the next best thing as the ECU is still optimised to suit your various individual modifications. Flash Tune not available for Cammed/Supercharged Cars.

Dyno Sheets

Below is the Dyno sheet from our original XAIR 2004 VY SS 5.7 ls1 Manual Wagon.

Bottom line shows Initial Power run stock. At the rear wheels it made 199.2kw & 356nm Torque.

We then bolted the XAIR OTR Intake on with the MAF In place and ran it up on the factory tune. Second line shows this power run at 220.9kw & 397nm Torque which is over an 11% increase. The difference in driving on the road is massively noticeable especially the increased throttle response. Plus we dropped an instant 2.2 litres per/100km in average fuel consumption.

Protune dyno'd the car before and after we fitted the OTRCAI. With the gains made they commented that the XAIR OTRCAI is the best value for money bolt on performace modification you can buy for V8 Commodore.

We then fitted HSV VY2 Headers and a Big Bore Exhaust plus Protune did a full MAFLESS Custom Re Tune. The top lines on the Dyno Sheet show the final power run where it made 250.5kw and 450.9 Nm of Torque which is a further 13% increase in power and torque. Fuel consumption has since dropped by a further 3.4 litres / 100km.

Power - Dyno KW vrs Engine KW

A lot of people ask why the Power figures generated on the Dyno Sheet are less than the Engine Power KW Badges.

Manufacturers quote Power of the Engine whereas a Dyno measures Power at the Rear Wheels. To allow for the driveline power loss and calculate power at the Engine we take the Rear Wheel KW Power figures from the Dyno and use the standard conversion of 25% (x 1.25) for Manual and 30% (x1.3) for Auto Cars - See above Dyno Sheet for Engine Power figures (in brackets) which are calculated by multiplying Dyno Rear Wheel KW x 1.25 being a Manual.

Note : No two dynos will measure the same so it's more important to look at the before and after figures for total gains/improvements made.