I have been looking and looking for a company to make a stronger trans for our cars.. I am going to contact a local should called Andrew Tech.. they specialize in custom stuff and mostly subarus..
However They deal a lot with transmissions.. I am going to give them a call.. I have a spare trans layin around Ill take it there and see what they can experiment with..
But i think one of th eproblems is the space inside our tranny's i dont belive there is enough room for larger syncros or gears..