A pertinent question I guess....
I run a 1UZ V8 FJ40 with 33 inch BFG MTs, 4.1 diffs and H150 5 speed gear box. I recently tried daily driving it to check how far I could stretch the economy bit. Was shifting very early, skipping gears and rolling out in 2nd from traffic lights etc etc etc on drives between Islamabad and Rawalpindi. The fuel ecomony figures were so good that I dare not mention them out here until I am able to double check them again
Anyhow what I am saying is that if one can manage it, the 1UZ is now a strong all-round contender for one of the best swaps in an FJ40! At least in my books i.e.
On tires stick to Yokohama / Bridgestone ATs and you can't go wrong as long as you get a fresh new Japanese set!