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Old 26th April 2022, 12:06   #71
macafee2
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Originally Posted by Torqueofthedevil View Post
I'm not going to try it, because cornering isn't a situation where I would let a car coast! Likewise, if I'm coasting and something happens and I need to brake, I can put the car back into gear in less than a second. But as per my previous post, in some situations (eg no corners, empty road - half a mile from a roundabout on a quiet dual carriageway might be one example) I don't see any harm in it at all.
You are not going to try it but say ".....and I'm not at all convinced that the supposed safety concerns have any validity." All you are left with is your opinion despite you being given an example test to try to see if your opinion is one you can prove or disprove to be correct.

Do you still think slowing in gear uses more fuel then coasting in "neutral"?

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Old 26th April 2022, 15:44   #72
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I would suggest simply to slow down gradually, making best use of the car's momentum while using minimal fuel, in a situation where best brake performance and cornering ability aren't needed.
I thought that fuel consumption would be behind this! Charlie, you've very reasonably and honestly said that you would only coast in limited circumstances. I would suggest that nevertheless any saving would be purely academic and so low as to be unmeasurable.

In any case, when you are slowing down gradually with your foot off the accelerator, the petrol 75/ZT will use minimal fuel anyway as the ECM is programmed to reduce the injector period.

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Old 26th April 2022, 18:36   #73
Torqueofthedevil
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Originally Posted by macafee2 View Post
You are not going to try it but say ".....and I'm not at all convinced that the supposed safety concerns have any validity." All you are left with is your opinion despite you being given an example test to try to see if your opinion is one you can prove or disprove to be correct.

Do you still think slowing in gear uses more fuel then coasting in "neutral"?

macafee2
Your stated safety concerns do not apply in the situations where I would consider coasting. Therefore your experiment is entirely irrelevant! An equivalent would be a blanket statement (not by me) that driving with the lights off is dangerous. I would counter that in some situations, driving with the lights turned off (eg daylight!) is absolutely fine - to which you would reply "Just you try driving with the lights off in the dark and see how well it goes". Would you be surprised if I declined to try it?

And yes, I suspect that slowing in gear uses (slightly) more fuel than coasting in neutral, because in the former case the engine is turning at higher revs, and therefore needs more fuel to stay running than an idling engine. But I'm happy to be proved wrong!

Last edited by Torqueofthedevil; 26th April 2022 at 18:50.. Reason: Attempt at clarification
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Old 26th April 2022, 18:42   #74
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I thought that fuel consumption would be behind this! Charlie, you've very reasonably and honestly said that you would only coast in limited circumstances. I would suggest that nevertheless any saving would be purely academic and so low as to be unmeasurable.

In any case, when you are slowing down gradually with your foot off the accelerator, the petrol 75/ZT will use minimal fuel anyway as the ECM is programmed to reduce the injector period.

Simon
You're absolutely right - on a single occasion, the difference in fuel consumption is minuscule. I would suggest (with no attempt made to compare fuel burn) that over the course of a year, or five years, a worthwhile amount of fuel might be saved, with minimal hazard. I might well be wrong! But many years of coasting in specific occasions, without any hazard or problem encountered, would seem to confirm that the hazards are as negligible as the fuel benefit!
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Old 26th April 2022, 20:05   #75
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If I remember, you can use the obd to see the instantaneous fuel consumption as you drive along.So all these posts can be put to bed if you check it out.
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Old 26th April 2022, 22:12   #76
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Hello Charlie,

Coasting, that is making progress with the engine disconnected from the driving wheels, is actually dangerous. Braking distances are increased markedly together with the tendency for the car to understeer to an alarming degree.

What is the point of it?

Simon
I coast everywhere.----Locally half my journeys are in neutral.---

67 years plus on the road with never an accident or even a near miss.

Could be that I enjoy driving and get pleasure at every moment at the wheel and not just something to get from A to B.--I constantly judge my performance and position on the road and that of other road users.

I owned two Austin Westminsters over a period of 14 years.--The gearbox had a freewheel attachment fitted which meant the car never had engine braking.
Taking my foot off the throttle meant the engine went straight into tick over.

The clutch was never needed to change gear you just put the gear lever wherever you wanted.--Brilliant idea but never used in modern times.

That started me into free wheeling every where.----
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Old 29th April 2022, 23:02   #77
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Originally Posted by macafee2 View Post
That is not engine braking as I know it. In an auto you can move the gear lever sideways and then push the gear lever forward to change down, you then release it and by either pushing forward again or pulling back will change down or up. Some autos have paddles on the steering column, one for changing down and one for changing up.

I was assuming lipsee was using one of these two methods.

macafee2
All I do is back off the gas,, drop into 4th(with the stick),, nearer say a roundabout drop to 3rd(usally doing 3ooorpm),, then brake ,, I reckon braking down in Drive just feels not being in control .When leaving the said roundabout I change up earlier then you would normally then you would in a manual car then when straight I put it in Drive,,press on the gas and let the g/box do the work,,I think thats the best way to get good MPG...
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