If this will be primarily a street car, then 3.91's will be pretty steep & you'll have a lot of R's at highway speed. In my case, I chose a higher stall converter & 3.23's. For me it is the best of both worlds. The TC gets the engine up to the power band quickly at low speeds but at highway speeds I'm able to have reasonable economy. Biggest issue I have is traction at lower speeds when I nail it. Steeper gears would only exacerbate that!
