But its a small Town car and probably geared accordingly, sitting at 75 For long peridods Is quite fast for a 1.4, it may even be on boost. If he wants better mpg he will have to drive slower.
Miles per Gallon
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But its a small Town car and probably geared accordingly, sitting at 75 For long peridods Is quite fast for a 1.4, it may even be on boost. If he wants better mpg he will have to drive slower.
I have never been able to beat the cruise for a consistently high economy average on either my S or SL class mercs. I guess some cruise control systems are better than others, but i really do not find these systems have given me an economy hit at all.
In fact i got 32mpg the other day, using cruise for almost the whole trip from Oxford to Bristol (SL500 7G Tronic). I really cant think i could ever beat that "manually"..
That simply sounds like a bad design to me then, mine for example messes around with the gears and torque converter to maintain speed down hill resulting in an infinite mpg readout. It rarely ever applies the brakes unless you hit a very steep hill.
Not found one either but it's basically the sloweest speed you can go in top gear
http://www.whatcar.com/car-news/fuel-economy-making-every-gallon-count/233124
Interesting results especially how quickly small engined cars nose dive on mpg as you go above 60mph.
I would guess the drag coefficent, weight of the car and peak torque all come into the equation for optimium mpg.
My theory for a reasonable speed is top gear at max torque rpm.
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Well it's not really bad design as such, in a manual car it's not exactly possible for the cruise control system to change gears to cope with inclines
I find the same with manual cars with cruise, using my own forethought I can achieve significantly better economy.
I can imagine this being negated somewhat by an automatic that can react in ways a manual can't and negated further by active systems that can adjust sensibly to traffic flow if necessary.
Yours is still bad for MPG though.
what you want is to coast down the hill (still in gear) and use the uphill to reduce your speed.
cruise can ever do this, which is why it's never more efficient than a person in control (someone without lead feet
)Yours is still bad for MPG though.
what you want is to coast down the hill (still in gear) and use the uphill to reduce your speed.
cruise can ever do this, which is why it's never more efficient than a person in control (someone without lead feet
No its not bad for economy, as this is exactly what it does, as i just explained
It cuts the fuel, and runs down hills holding in gear, showing an infinite economy readout, if the car needs to slow more it shifts a gear and holds it in that gear. As an absolute last resort it will apply the brakes but that is very rare.In short, it drives as you would, and is as economical as i would ever imagine being able to drive.
No its not bad for economy, as this is exactly what it does, as i just explained
In short, it drives as you would, and is as economical as i would ever imagine being able to drive.
Where that will still lose economy though, is that it's trying to restrict speed downhill to say 70 still, whereas using your own insight, if you saw an uphill, it would be more prudent to let it stray to 80 downhill and use that extra momentum to keep more speed back uphill - something a cruise system can't do.
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Where as if i was driving I would let the car collect some speed such that it could bleed it off at the next uphill. In the meantime the cruise control is messing around with gears and stuff like the throttle to maintain the speed up a hill.
The only clever cruise control systems would be integrated to sat nav.
It's been my experience that diesels generally suffer less variable MPG when in town or A roads, yeah petrol cars can now return pretty good MPG figures but it seems thats only on longish journeys. I tend to have a nosey at every car that comes in to the garage's average MPG if it shows it, and the vast majority of petrol cars are low 30's and under.
I generally find in my own car that 50mph and 80mph are only about 5mpg different, 50 seems to slow for general B roads and 60mph does seem to be a sweet spot for my car, with even 100mph giving 42-43mpg.
I guess the point is, ignore what the manufacturer says, just experiment yourself.
I generally find in my own car that 50mph and 80mph are only about 5mpg different, 50 seems to slow for general B roads and 60mph does seem to be a sweet spot for my car, with even 100mph giving 42-43mpg.
I guess the point is, ignore what the manufacturer says, just experiment yourself.
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No its not bad for economy, as this is exactly what it does, as i just explained
In short, it drives as you would, and is as economical as i would ever imagine being able to drive.
You didnt explain, you theorised.
If you dont press the throttle you will cut all fuel in most cars today.. ie infinite mpg. Difference is in a high gear the pumping losses are not significant. If you drop it a few gears to increase pumping losses and friction then you will hold the speed as the engine braking retards the speed build up. All you are really doing with that energy is rather than gathering kinetic energy you are heating up air and oil in your engine. Its no different to heating your brake disks its still wasted energy.
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My journey to work this morning. Traffic is not my friend.
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My journey to work this morning. Traffic is not my friend.
What car is that? Older Audi A3?
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B6 S4
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