Originally Posted by adc

Back in the old days (of carburetors. I believe running low rpms and low power. The engines I believe were very inefficient bc of the lower pressures on the suction stroke (Throttle almost closed). They were way more efficient at WOT. That is not to say they didn't suck more gas at WOT lol.

Has new technology changed this somewhat?

Again another pitch for very very low displacement engines to keep air flow higher and reduce sucking losses.

I find that keeping my rpm 2000 or lower even during shift points (auto) and driving usually about 1600 or so in town gets me 28 mpg. The problem is it is harder on bearings. I have done a Used Oil Analysis (UOA) on the subie and its way better than my UOA on my 01 Sentra 2.0 SR20DE.