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Hey Vigge, glad to see you're still at it!
A few questions regarding the graph that you posted above:
1. Why bother to graph acceleration vs. rpm when acceleration already is a=(Vf-Vi)/t and you aren't using equal rpm startpoints? I'm having a hard time in seeing the value of that representation instead of just plain old acceleration where someone can easily compare the various rates by their respective slopes? What does the same data look like when graphed d/s vs. time?
2. What was happening during the periods when the acceleration is zero for all 3 data sets? If the data was logged from 70 to 150 kph for all plots wouldn't the acceleration curves all start at the same respective rpm's?
3. In order to meaningfully compare runs to one another wouldn't the beginning ground speed (and thus rpm's) have to be equal? Do you have enough data to show entire runs, all starting at X rpms with a mash to WOT at T=0? I think that would provide a great picture into the overall response.
4. To me, it looks like you've proved your point (provided all outside conditions, full tank of gas, same passenger situations, etc. were all the same). Would you be willing to show a graph of speed vs. time? Or possibly convert the above RPM back to ground speed for acceleration vs. velocity?
If I'm interpretating the data correctly it looks like both of the adapted runs gave more fierce acceleration (larger rate of change per rpm) over a more narrow amount of time but the new turbo, unadapted, ultimately was able to accelerate the car faster but at a lower rate of change. It's good to see that after adaption the slope of the acceleration curve nearly matches that of the 28...the 30 likely needing the higher flow rate from higher rpm operation to reach it's area of operation efficiency but then experiencing flow limit decreases from T7. For sure post some followup comparisons after you get the software to keep that bad boy in it's efficient operating island. Are you sure that your A/F was good with the 30 before adaption? Don't know why it would cut timing...what did your manifold pressure look like during the above? Did it allow for an overshoot?
Don't know what your data logging capabilities are but it would be great to see a plot of acceleration vs. manifold pressure and acceleration vs. flow over top of intake temps.
posted by 67.10.2...
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