The guys at TS are great and really know what they are doing with the ECU. I may suggest waiting to do it if you dont have other engine modifications (headers, intake exhaust , cams) you will see a bigger improvement.
The 3.9 is what the track model 350Z should have come with. Its a mod that anyone doing serious tracking/autocross or jsut spirited street driving can really enjoy. There are planty of people out there with this modification.
Any questions just let me know.
BJ@350EVO.com

 

any chance 350evo would come out with a 3.7 final drive for auto owners? im sure even some of the 6mt guys worried about too much mpg loss may hop on board too.

 

The auto guys would bennifit from the 3.5 thats in the manual. Mine is going in soon and I will report back.

 

Can someone type in the mph shift points with and without the 3.9 final gear. My redline is raised and I am wondering will I have to shift to fifth gear going down the 1320. Thanks