Renew-Reuse-Recycle | Re: How do you determine the most efficient speed to drive your car at on a motorway.

Re: How do you determine the most efficient speed to drive your car at on a motorway.

by Stuart at 2008-02-27 15:28:33 (Forum::Public::Transport)

Thanks muymalestado, would it matter what type of sandwiches I took?

"My Rover with a 1.8t engine is doing 2200 rpm at 55mph in 5th gear. Rising to about 3000 rpm at 75mph, and I imagine 3750 rpm at 90mph! "

Lets have a look at this a different way. By dividing the speed by the rpm we should get an idea of efficiency (assuming each engine revolution uses the same amount of petrol).

The results are:
At 2200/55mph each rpm gives .025 mph
At 3000/75mph each rpm gives .025 mph
At 3750/90mph each rpm gives .024 mph

So it appears linear. So why does every one say that efficiency decreases dramatically with speed?

--
Stuart

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How do you determine the most ...	Stuart - 24/02
Re: How do you determine the m...	Colin - 27/02
Re: How do you determine the m...	muymalestado - 27/02
Re: How do you determine the m...	Stuart - 27/02
Re: How do you determine the m...	muymalestado - 27/02
Re: How do you determine the m...	Colin - 28/02
Re: How do you determine the m...	Simon Ridout - 1/03

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