Background:
After concluding a series of tests with the Shuenk IS48 turbocharger, which culminated in a power tune that peaked just over 440 whp, I wanted a tune that would not use any ethanol beyond what is in pump 93 octane gas and generate less power, so that I could resume making full-throttle pulls in third gear.
Russell Road & Racing has been adjusting the ECU for the various test goals, and for this request, they dropped boost pressure and ignition timing. This tune is labeled version six (v6).
I also swapped back to the Baun Performance GESi catted downpipe from the Trackslag catless because I don’t care for the smell from the catless downpipe.
Test Procedure:
Full throttle third gear pulls beginning around 2,500 RPM and concluding around 6,500 RPM were made to collect performance data.
Test Results:
Ethanol content was not quite down to the 93 octane fuel level of 10%, sitting at 16%. This is significantly lower than the 48% ethanol that the version five (v5) tune data was recorded using.
As mentioned, v5 allows me to log using 3rd gear, where the higher power output v5 tune requires data collection to be performed in 4th gear.
Boost pressure builds sooner in 4th gear on account of the longer time that the car takes to accelerate. The chart below shows the reduced boost pressure with v6.
WGDC is slightly lower using v6. The lower boost pressure should produce this, but there is some offset caused by the catted downpipe.
Ignition timing is reduced significantly with v6.
AFR is very similar, as expected.
Acceleration rate with v6, taking advantage of being in third gear, is increased.
Virtual Dyno power and torque curve with the v6 tune are shown next.
vDyno Peak WHP Trend is shown next, with a median peak WHP of 354.
The IAT delta at 6,000 RPM trend is typical for the current setup, which is an IE V1 intercooler combined with a Vibrant FMIC.
Finally, an approximation of where the tune puts the IS48 turbocharger on a similarly sized turbocharger compressor map
Conclusion:
The 93 octane tune meets my goal for being able to operate with 93 octane fuel and conducting data logging in third gear.