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Old 28th September 2019, 10:03   #41
wraymond
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Just caught up with this thread, I'm one of those that couldn't care less about mpg so rarely follow. I just enjoy the car and fill up when it gets to 1/4 tank.

However, the major factor that has so far been largely neglected is on the Revs. With the auto box a weighty right foot that reaches the speed limit quickly, then coasts, destroys realistic calculations.

On the other hand, keeping the revs to reasonable rev limits, in other words moderate progress and in my case under 2500 rpm, will give reasonable consumption. That's how cruise control gets better figures if that's what you want. Switching to sport and kick-down will destroy economy but in my view if you want increased performance that's the price.

Incidentally, most sensations of speed are affected by subconscious needs for excessive right-foot over-use. Check your throttle cable slack at the swivel end. If it has brewer's droop you are losing travel in taking up the slack with your foot. That means you have to drive with increased foot pressure! Adjustment couldn't be simpler and the effect is a magical response.
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Old 28th September 2019, 10:21   #42
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Its just about 1 mpg more than the MGRover figures so allowing for possible variation at the pump in spite of my best efforts I think it is a fair figure- I wasn't exceeding 65mph on the motorways and sometimes a bit less so all in all Im happy with the figures. The conditions make a difference to everything and of course I had "Stocktake" check the VIS motors at the nano and he put his magic finger on the accelerator cable!!. Chris S.


I have these to go in, weather permitting. I recently sent Dave my old ones in exchange for the latest upgrade. A fast turnaround, thank you very much Dave and thank you Rover54, for the loan of a spare set.

I am wondering if I can get the mileage back up to 42mpg. (Kaiser, no need to answer) It is achievable and that’s without placing an egg under the accelerator or any other dastardly mischievous trickery At the very least, I am looking forward to an improvement.
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Old 28th September 2019, 10:40   #43
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I am wondering if I can get the mileage back up to 42mpg ... It is achievable ...
Is your car manual Phil?

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Old 28th September 2019, 11:15   #44
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Is your car manual Phil?

Simon
Auto is the answer. Simon, what is your opinion of the display on the dash which gave me the reading of 42 mpg, I add whilst cruise control was set to 55 mph on the motorway. The 42 mpg was not constant.

My question to you Simon, is the display on the dash, accurate/reliable for mpg and mph?
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Old 28th September 2019, 14:33   #45
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... what is your opinion of the display on the dash which gave me the reading of 42 mpg, I add whilst cruise control was set to 55 mph on the motorway.
Am I right Phil, in my suspicion that you reset the display as you set your cruise control at 55 mph, and after a short period it read 42 mpg?

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Old 29th September 2019, 10:05   #46
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Am I right Phil, in my suspicion that you reset the display as you set your cruise control at 55 mph, and after a short period it read 42 mpg?

Simon
You are correct Simon.
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Old 29th September 2019, 15:08   #47
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Incidentally, most sensations of speed are affected by subconscious needs for excessive right-foot over-use. Check your throttle cable slack at the swivel end. If it has brewer's droop you are losing travel in taking up the slack with your foot. That means you have to drive with increased foot pressure! Adjustment couldn't be simpler and the effect is a magical response.
The Magical Effect is due to muscular memory retention.

Your foot goes to its normal cruise position but in fact, with the slack out of the cable, you are actually giving the car MORE throttle.

A cheap tune up for an increase in your subjective assessment of your vehicle.-----





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Old 29th September 2019, 16:10   #48
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As ever Jon, the psychological triumphs over reality! Then, reality kicks in and the foot eases back giving a marginally better mpg. Or, it feels like it.
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Old 29th September 2019, 19:31   #49
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Always an interesting debate as to whether getting a car up to cruising speed quickly gives better economy than gently getting up to speed.

Obviously booting it drinks fuel but then you can back off sooner. Not booting it uses less fuel but then you spend longer getting into top and, as you journey takes longer, longer with your engine running & therefore burning fuel.

In theory you engine is at its most efficient when at maximum BHP (which is well up the rev range) but that's efficient as in juice vs power and once you are at the desired speed you don't need the power.
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Old 29th September 2019, 21:44   #50
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You are correct Simon.
Thanks Phil. What you are seeing there is a "snapshot" of your fuel consumption at a steady 55 mph. Now zero the display just before a cold start and tell me what fuel consumption is shown immediately afterwards.

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