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I was searching for gear ratios for a bunch of toyota, honda, and hyundai manual cars and I only found two cars that weren't running 2500rpm at 60mph - the accord and camry, which doesn't help because they're (relatively) huge cars with large engines. Does anyone here know of a new vehicle, with reasonable gearing, that doesn't have a 2.2 liter or so engine?

That said, how does a larger engine at a lower rpm compare to a smaller engine at higher rpms? i.e., Does a Yaris 1.5L, at 2600rpm, get the same mpg at the same speed as a 2~2.1L engine at 1900rpm?

I'd say it's a little better. The new EPA tests really destroy FE in the new compacts because they run up to 80 MPH which in the Yaris and Fit mean 3600 RPM for the Yaris and nearly 3900 for the Fit which is simply ridiculous. There's a reason why the Corvette can get over 30 MPG highway even with a gas-guzzling V8 engine and that's because it has an extra tall sixth gear.

My FIT auto runs about 2100 rpms at 60 mph.

I'd say it's a little better. The new EPA tests really destroy FE in the new compacts because they run up to 80 MPH which in the Yaris and Fit mean 3600 RPM for the Yaris and nearly 3900 for the Fit which is simply ridiculous. There's a reason why the Corvette can get over 30 MPG highway even with a gas-guzzling V8 engine and that's because it has an extra tall sixth gear.

And that is why I don't like these tests. They don't really tell the whole story. I want a simple graph of speed vs mpg. Make it for a flat road, no wind if you want. Then tell me fuel consumption on acceleration. Then I can pick a car that is most efficient for the speeds I drive. I don't do 80 and I don't zoom away from stops, any test that includes those elements, like the new EPA tests, distort the information I need to make a good choice of vehicles.

Something that you are not taking in to consideration is Engine load, and Fuel injector fuel cycles.

Just beacuse an engine is moving at 4000 RPM does not mean is using more than an engine at 3000 rpm.

if the engine is runing without effort at 4000 rpms and creating more than sufficinet power for the load, then then injectos are at low duty.

if the engine is not creating power and have high load at 3000 RPM , then the injectors will inject more fuel , than the other engine at 4000 RPMs

damn engeniers and their complicated systems. its not too easy to figure out.

So no worries about buying car with tallest final gear ratio. find lowest load for rpm & speed.

AKA . POWAAAR :) hehehehe ( you see highperformance cars can be more economical than some other low powerd cars )

My Yaris Auto must be special or something, because at 60 I'm running at 2100 rpm, while at 80 I'm only doing 2900...I wonder if the manual trans is geared differently...

Most auto trans and manual trans are geared differently even on the same year make and model car.

My Yaris Auto must be special or something, because at 60 I'm running at 2100 rpm, while at 80 I'm only doing 2900...I wonder if the manual trans is geared differently...

Manuals are geared shorter because some ****ing Einstein at the automakers thinks shorter gearing will make the car seem sportier (quicker acceleration). Fact of the matter is a four cylinder is a four cylinder, and by making gearing really short it's just destroying the potential FE in any vehicle.

If I'm doing 60 MPH I'm likely around ~2600-2700 RPM. I don't know for sure because I haven't been up there in a long time. :o

my 08 civic(auto) holds 60 somewhere between 1500 n 2000, cant remember. 75 at 2500, and 90 at 3000RPM :-P

my 08 civic(auto) holds 60 somewhere between 1500 n 2000, cant remember. 75 at 2500, and 90 at 3000RPM :-P

Daaay-um. I can barely hit 1500 below 40mph. Now that is some nice gearing :)

So no worries about buying car with tallest final gear ratio. find lowest load for rpm & speed.

AKA . POWAAAR :) hehehehe ( you see highperformance cars can be more economical than some other low powerd cars )

This is only true in a very simplistic viewpoint. A glance at a BFSC chart for an engine will tell you why. You will (almost) always consume more fuel at a higher RPM / lower load than at a low RPM / high load.

Internal engine losses due to friction are related to the SQUARE of rpm. As rpm rises, power wasted to friction also goes up.

This is why a tall geared transmission that places you at a low rpm and high load is optimal for FE.

Ideally, you want an engine that will only produce enough power to keep you moving at your maximum rate of speed while at the point of best BSFC.

Unfortunately, this engine would only have like 30 hp and it would take a looooooong time to get to that speed. So we have to compromise already. :)

Manuals are geared shorter because some ****ing Einstein at the automakers thinks shorter gearing will make the car seem sportier (quicker acceleration).

Clearly you haven't driven many *real* sporty 4 cylinders. A tight, short transmission absolutely does make even the most underpowered car much faster. An ideal transmission allows you to accelerate as quickly as needed in the lower gears, with a nice, tall 5/6 gear for cruising.

Making 1-2 very short for good acceleration is a good compromise - how much time do most people spend in those gears anyway? Very little.

So what about a 6 speed manual like the Pontiac Vibe GT? Does it still rev high in 6th?

I'll see what I can find, but have never researched for gear ratios before or done that math (other than bicycles...).