Give Detroit Speed a call, their 5th gen test car runs a mast motorsports LS3 with the harrop intake. I was looking at it a few weeks ago, they said it sure was hard to tune, but they got it right in the end.
Other than that, checkout the Australian holden forums. They may recommend a Haltech ECU
Brian Hobaugh SCCA National Tour June 2014
First Hemi 'Cuda Convertible Ever Built
Short clips: Goodguys Pleasanton autocross and pit videos
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