I have an Insight build going on with an 08 Fit engine, I’ve been looking at the less than desirable gearing and what I can do about it and I found the 03-05 Civic Hybrid has the same exact trans with exception of the gear ratios as well as the bell housing side of case. This means you can use the 5th gear from the Civic as many do with the TSX 6th in the K series. 3.6 FD will swap in as well for the turbo guys, maybe. I will be using all the gears from the Civic myself.

Here is a link to the thread with details Honda final drive expert help needed. - Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com

 

Oh wow, there is hope! Subscribed.