One of the upsides to switching back to a pair of BW K03 turbochargers will be the opportunity to more fully log the performance of the vehicle with those turbochargers installed.  The last time my car had K03’s installed all I had to log with was VAG-Com.  This time I’ll be utilizing some more capable data logging software as well as bringing some additional sensors into the mix.

One component that I’ve had for a while is the Innovate LM-1Air/Fuel Ratio monitor and data logger.  I also purchased the Innovate RPM converter (LMA-2) which can be used with an inductive pickup, but of more interest to me, allows 4 additional sensors to feed into the LM-1.

An additional input that I like to have is a stand alone manifold air pressure (MAP) sensor.  Since I already had the LM-1 I decided to stick with the Innovate products and add the Aux Box (LMA-3).  This device can provide data from 5 sensors, either the built in sensors or external.  The unit comes with a 3 BAR MAP sensor, EGT, RPM, Injector Duty Cycle, and a 2-axis accelerometer.  Alternatively up to 5 external sensors can feed through the Aux Box, and of greatest interest to me since the LMA-2 does not have this capability, the Aux Box can provide up to 300 mA of 5V power to the external sensors.  This means I can just get additional sensors and not have to worry about control boxes, so long as the power requirements are appropriate to the Aux Box capabilities.

A fast responding intake air temperature sensor is something I’ve wanted for a while and the Auber instruments sensor and controller combination fit what I was looking for.

Finally, while not strictly a sensor box, the Eurodyne BoostManager water injection system includes a 6 BAR MAP sensor which I will find some use for.

The chart below shows an approximation for how the stock B5 S4 intake system compares against an aftermarket alternative.  The various system components were tested separately, so the composite results shown below do not accurately depict how all of the parts would measure if operating on the automobile.

Additionally, when on the vehicle the operating pressure would in many cases be much higher, which would cause the pressure losses to be greater.  Still, the chart gives some indication to the scale of improvement that can be obtained through the use of aftermarket or alternative parts, at the tested airflow of 500 CFM.

The legend shows the different configuration tested.  To the left of the slash ( / ) is the stock configuration and to the right is the modified and/or aftermarket configuration.

The following information is a summary of data I have personally recorded as well as information I have obtained by viewing the results provided by others.

This information should not be taken as ground truth, there can be variability in results dependent upon how a car is operated, what environment it is evaluated in, and how the information is collected.  The point of presenting this data is to make available to others the information that I use.

In the following scatterplot, products for which I do not have IAT data are shown along the vertical axis at an IAT Rise value of zero.