I was running a 1UZ with a 3.9:1 (LSD) rear ratio (4.11:1 around town) with an overdrive A340E trans, K&N Air Pod Autronic, extractors, free flowing exhaust, stock internals but mix that with a quite heavy foot and I average around 16-18mpg.
400km (250 miles) for every 65 litre (17 gallon)...