Edmunds reviews Mazda CX-7 SUV

spwolf · 2006-04-21 20:04:33

:) :) :) :) :) :) Everyone. Good discussion. Praise from Caesar. :D

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04-25-06, 09:37 PM

#31

bitkahuna

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Quote:

Originally Posted by 1SICKLEX

Everyone. Good discussion.

Praise from Caesar.

04-26-06, 06:02 PM

#32

SteVTEC

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Quote:

Originally Posted by spwolf

Really? I doubt it. Difference in mpg is much greater than weight actually. Plus it has to use premium. Plus it has narrower usage range. Plus it has worse emissions. And costs the same.

10% less weight is helpful for mpg when accelerating, but EPA tests are not done accelerating at high rates, but cruising. At that point, more relavant is aerodynamics, gearing, engine itself.

You do not even understand basic physics. Doesn't really matter how quickly or slowly you accelerate because in EPA tests that's already pre-determined. A heavier car requires more energy to accelerate to a given speed than a lighter one, and thus will consume more fuel doing so period.

Quote:

Originally Posted by spwolf

But what it comes down to is that CX-7 has 4cly turbo and Rav4 has V6. And yes, Rav4 is lighter vehicle.
Thats the fact that cant be changed.

Is Toyota's fault that they engineer car to be lighter? Toyota spent millions to engineer new AWD system that was 40% lighter than one used before.

And what about that lightweight? The US market is the only one to get the V6 yes? Was it properly reinforced? Will there be lots of chassis flex? Will it become a rattle trap because it lacks the rigidity and stiffness needed? Will it have a solid driving feel? More powerful cars are often heavier not just because of added engine mass, but due to everything else getting beefed up to handle that along with it.

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Originally Posted by spwolf

As I said before, engine itself really can not be seen on its own.

Think outside the box and it can be.

04-27-06, 06:23 AM

#33

mmarshall

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Quote:

Originally Posted by SteVTEC

Doesn't really matter how quickly or slowly you accelerate because in EPA tests that's already pre-determined. A heavier car requires more energy to accelerate to a given speed than a lighter one, and thus will consume more fuel doing so period.

Maybe.....not necessarily. Depends on a number of other factors as well.....transmission and final drive gearing, engine displacement, how hard the engine actually works, rolling resistance of the tires, how much you slip the clutch ( on a manual transmission ), fuel octane and spark timing, etc.......

04-27-06, 08:02 AM

#34

SteVTEC

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all other factors being equal or roughly equal (and in this case they most likely are), the heavier vehicle will require more energy to accelerate up to a given speed.