After utilizing a pair of 1mm Aquamist nozzles with my BorgWarner K03’s, a case of overkill that resulted in some misfiring due to an unnecessarily high volume of fluid being injected into the engine, I scaled back to a pair of Aquamist 0.7mm nozzles.

At the same time I was also beginning to utilize larger turbochargers, thus getting closer to a proper matching of components.

I’ve been operating with the 0.7mm nozzles for a while and through the ability of the Torq Tune software to enable me to tightly control the injection pump duty cycle I’ve been able to find a DC that has been producing good results.

I have been wondering if running the pump at a higher duty cycle, but with a smaller nozzle, would keep a similar flow rate at a higher system pressure.  The thought being that I may be able to obtain better atomization of the liquid with the quantity of liquid remaining the same.

To try and see if this is a valid idea I’ve obtained a pair of Aquamist nozzles in the 0.4mm size.

I’ll be assessing the flow rate through these nozzles versus the pump duty cycle, and then it will be onto the street to see how the Intake Air Temperatures change with smaller nozzles, hopefully at a similar flow rate to what I have been operating the 0.7mm nozzles at.

There are a few bits of interesting data that I’ve recorded while measuring boost pressure for fixed wastegate duty cycles.  This is part of my effort to fine tune the KFLDRL numbers for the new wastegates that the TTE550’s use.

Each fixed wastegate duty cycle produces a different boost level.  The range of boost levels that were recorded in third gear are shown below.  Note: The recording in third at 10% was not long enough to make including the results worthwhile.

The chart above shows fixed WGDC’s of: 0%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, and 85%.

For each of these boost levels I also recorded the air temperature going into the turbocharger compressor, along with the temperature after exiting the compressor.  The approximate rise in temperature caused by the compression of the air for each boost level is shown below.

Note: This is an approximate rise due to the location of the air temperature sensor being slightly downstream from the turbocharger compressor outlet.  The air temperature exiting the turbocharger is likely higher than what is recorded due to cooling taking place in the charge pipe prior to the air passing over the temperature sensor.