Originally Posted By: rationull
This has already been touched on but unless I missed it, not stated explicitly yet. Along with tire pressure etc, and especially driving style, gearing will actually have a reasonably sized impact on fuel efficiency. Gas engines are most efficient at low RPM and high load, within reason of course. Civics (especially with manual transmissions unless you're talking an HX model) tend to be geared more for pep in top gear than for fuel economy.
I can't remember the specific numbers for the Accord, but where my Civic (1.8 liter) is geared to turn about 3000 RPM at 65 mph, the same year Accord with the 2.4 will turn around 2500 RPM, IIRC. I imagine the Camry is geared similarly to the Accord. I think the Corolla is geared a little bit more conservatively than the Civic.
Anyway, that's part of the picture too.
Excellent point!!!!!! Here is my example.
The older 1995 Civic CX 1.5L I4 seems to be geared for efficiency - higher ratio. I know it simply because it is slow to accelerate and people are passing me all the time from a stop sign or a red light. However, I get 40 mpg and when I try little bit (like lower speed and such) get 60 mpg this summer on highway.
2003 Mazda Protege5 2L I4 doesn't seem that much different. Sure bigger engine and bigger/heavier car, power steering/breaks, etc. However, it is around 30 mpg and when I try I may get to 34 mpg.
While Civic has no tach, Mazda is well into 3K by the time I get to 60mph. Thus Civic will handle higher speed fairly well due to high gearing AND low CD, while Mazda is not so good. Of course, that is until small Civic's 1.5L starts to scream around 70 mph or so, so I try not to go that fast.
There are a lot of factors. In general lower speeds and keeping tach around 2K and below 3K gets you the best efficiency.
The main issues I find with the newer cars is lower gearing for more torque, highe CDs and power everything (stearing, breaks, windows, etc.)
This has already been touched on but unless I missed it, not stated explicitly yet. Along with tire pressure etc, and especially driving style, gearing will actually have a reasonably sized impact on fuel efficiency. Gas engines are most efficient at low RPM and high load, within reason of course. Civics (especially with manual transmissions unless you're talking an HX model) tend to be geared more for pep in top gear than for fuel economy.
I can't remember the specific numbers for the Accord, but where my Civic (1.8 liter) is geared to turn about 3000 RPM at 65 mph, the same year Accord with the 2.4 will turn around 2500 RPM, IIRC. I imagine the Camry is geared similarly to the Accord. I think the Corolla is geared a little bit more conservatively than the Civic.
Anyway, that's part of the picture too.
Excellent point!!!!!! Here is my example.
The older 1995 Civic CX 1.5L I4 seems to be geared for efficiency - higher ratio. I know it simply because it is slow to accelerate and people are passing me all the time from a stop sign or a red light. However, I get 40 mpg and when I try little bit (like lower speed and such) get 60 mpg this summer on highway.
2003 Mazda Protege5 2L I4 doesn't seem that much different. Sure bigger engine and bigger/heavier car, power steering/breaks, etc. However, it is around 30 mpg and when I try I may get to 34 mpg.
While Civic has no tach, Mazda is well into 3K by the time I get to 60mph. Thus Civic will handle higher speed fairly well due to high gearing AND low CD, while Mazda is not so good. Of course, that is until small Civic's 1.5L starts to scream around 70 mph or so, so I try not to go that fast.
There are a lot of factors. In general lower speeds and keeping tach around 2K and below 3K gets you the best efficiency.
The main issues I find with the newer cars is lower gearing for more torque, highe CDs and power everything (stearing, breaks, windows, etc.)
