Just ended a great weekend of semi truck racing.
On my agenda where testing the hi pressure fuelpump and able to get some more fuel out making some modifications on the XPI fuel system but still 300 to 500Bar or 4351 to 7251PSI short on fuel pressure to support the hi flow injector.
The better the fuel injection system get the more critical begin injection will become and
CR did play a bigger part in this as expected. The two race engines are still stock so fairly hi compression ratio compared to the rally engines we build last year but manage to get a load more power drop EGT 50 degrees went from a 18AFR to a 16 AFR fuel ratio just by injecting more fuel in a shorter time due to hi flow of the injector but still the goal is to hit 14.7AFR so 1.3 parts of air need to be burned by getting the commonrail fuel pressure up so bigger fuelpump needed. So very happy with the results and able to use them on the V8 puller engine as well but looking into replacing the hi pressure pumps ASAP as the engine is still under repair from the small end damage to the pistons and as new part are made for this we now have some time left to make changes.
This is how you test an engine using the rear breaks and read the data from the ECU and walk away with a smile thumps up problem fixed.
Plump injector setting on the ECU. Only start of injection and injection angle and that’s it for fuel timing and metering as the rest of the calculation is done by the ECU. Also this calibration as the option for two power settings.