nyt kun taas jouduttiin tähän kulutuskeskusteluun niin ihmettelen useasti miksi aina on se harhaluulo että alhaisella moottorin kierrosluvulla on jotian tekemistä taloudellisuuden kanssa, enemmän kait vaikuttaa sen moottorin ominaisuudet
itse en kykene hienoihin tieteellisiin kaunopuheisiin joten ei siitä sen enempää mutta jeepin osalta lainaan tähän tuolta obamamaasta
the 4.0 needs to be at an absolute minimum of 2400 and preferably in the 2600-2800 range at 70 mph. Lower is not better in this case. The 4.0 reaches the point of peak volumetric efficiency at about 3100 RPM, so running closer to that is more efficient than lugging it. Regardless, you can't expect to get acceptable fuel mileage at 70 mph due to wind resistance, even if optimally geared. After about 60 mph, the dropoff is sharp
Volumetric efficiency. An engine is nothing more than an air pump. Due to things like valve timing, valve configuration, port size and length, etc, etc. the engine will pump the charge in and out at the most efficient rate, at a given RPM. You usually see the VE
Couple that with the amount of power to keep the vehicle moving (gearing) and you produce a likable set up.
Not to be confused with peak HP and torque. If your building a dragster, you want the engine spinning at peak HP at the end of the run. You gear for that. On a torque vehicle, you gear to be driving at peak torque. Cruising you want the vehicle at the bottm end of the peak VE curve.
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