I've read that performance tunes alter the shift points and pressure only while the Automatics are in "D"; the "S" mode is unaffected. Has anyone done or received a tune that also changed "S" mode performance? I've spoken with a big name tuner and was told they would have to check into that and get back to me...but it's been a while!

 

"S" mode in my '14 GT is much more aggressive with the SCT "strategy" tune I recently installed in my '14 GT. Drive is also more aggressive, although shift points aren't as high as I want, so I use "S" at the drag strip to get to 7,000 rpm's.