Bought a set of ~3.5:1 gears to stick into an extra S13 240SX diff. (4.08 are common/stock) Good for a high-torque engine swap should I do one at a later time... and if the little motor I stuff into this one seems like it can pull the load with that much more gear, I'll give it a try.
In my opinion this has given my S13 a firm advantage for the MPG project over doing the same engine/trans swap to the RX-7.