the NWH20 had an inverter to step up the voltage, since the classic is lacking that inverter to boost up the voltage wouldn't that be a critical part of the system as well?

i got around 20 km a liter when i drove a civic 5 spd using advanced hypermiler techniques
and now I drive a salvage nwh20 prius that gets almost to 25 km/l with 195,000 km to date.