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Old 11-04-2012, 05:32 AM   #34 (permalink)
euromodder
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Quote:
Originally Posted by wobombat View Post
I normally pulse up hills and glide down them, but then I realized that putting cruise control on would do pretty much the exact same thing.
The most efficient - but not always the most practical - way is to slow down going uphill.
You trade kinetic energy for potential energy (due to being higher) and can get (most of) the potential energy back while going downhill.

That's exatly what a CC does NOT do, as it tries to maintain a constant speed.
So uphill it's pouring on gas, downhill it's engine braking (throttling back).
Both are inefficient ...

I try to pulse before an incline, then coast up it and down again - works for bridges etc, but not on hills as the climb is too long.


Long climbs on CC can become highly inefficient if you "overload" the engine - which I can do on my tiny 1.6 L turbodiesel.
It WILL pull up the hill, @ 100% (relative) LOD on the ScanGauge, but it comes at a cost : diesel.
Some 20-30% more of it than when going 20kph faster !
And at triple to quadruple the "level" FC.

Thus, going uphill faster on CC, can actually be more efficient than going up slower on CC - simply because it doesn't load up the engine that much as the rpm are a lot higher.

This is a case where big US engines will do relatively better - simply because they can cope better with the temporary higher load.


Quote:
And considering that a hill puts a constant backwards pressure on your car, wouldn't you save the most gas by getting off that hill as soon as possible without going too fast as to lose efficiency to air resistence ?
Drag is the permanent loss in our real-life system.
More speed = more drag , both air and mechanical
So the faster you go, the more drag you'll have.
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