RPMs and MPG

Just got a question, prolly dumb, but im curious and dont know who to ask

Heres a list my RPMS at certain speeds: (01 Grand am 2.4L auto)

65mph = 2100RPM

75mph = 2500RPM

80mph = 2600RPM

85mph = 2700RPM

90mph = 2900RPM

I guess my question is, although gas mileage, per gallon, decreases after 65mph(rumor?)....wouldnt using an extra 500RPMS(80mph) to go an extra 15 miles be good? hope this question makes sense..

Frank

Well it almost evens out. Cause your increasing fuel usage but your also increasing the distance you've traveled with that fuel.

John

yeah, I agree with formula, your rpm range is right for the trans. and speed you asked about, so it only how the car runs in those ranges. If you are concerned about mileage, the 2.4 tends be be most efficient in the 2-3K rpm range on the highway.

thanks for the input!