The question I have is this, Mikels reworked the E67 for the Lous Change car, and I thought that was a GMPP harness and ECM for the LS9, so what did he do that you didn't?
Lou's car is an LSA, maybe that matters, but yeah, I've been wondering the same thing myself.
Yesterday, I transferred the tune from the old GMPP file to the new ZR1 OS tune file. I moved every single table, one by one, and did a complete audit of all the DTC codes and their behaviors. The end result was unexpected, in a good way.
I finally fired up the car, monitoring all the usual parameters, including fan desired/fan %/AC pressure.
With an identical tune (as near as I can tell) the car runs better. The idle is smoother, throttle response is better, TPS % at idle is better (27% to 19%), fuel trims are markedly improved, and O2 voltages are smoother.
There's no doubt the car runs better with the ZR1 OS than with the GMPP OS, with an identical tune. Oh, and the fans function perfectly. AC and ECT desired both work exactly as documented.
Anyway, after 4 weeks' delay, the project is back on track. I'll never use a GMPP crate controller or OS again. From now on, I'll make my own harness, and get my own controller.
Brian Hobaugh SCCA National Tour June 2014
First Hemi 'Cuda Convertible Ever Built
Short clips: Goodguys Pleasanton autocross and pit videos
Hybrid Mode
