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A question for 75ps owners. What cruising speed on the motorway strikes the right balance between economy, comfort, stability and speed?
spud said:I think you 75 owner are a little unfair on the 60 as I get exactly the same and I have cruised at 100 comfortable with 45mpg
matt-drummer said:`Thinking about it, surely the bog standard Up! would be slightly more relaxing as the engine won't have the a/c unit to cope with, meaning slightly lower revs at any given speed?'
How? Having air conditioning does not make the engine rev more, it just takes power from the engine, the car is geared the same with or without air conditioning.
Just to clarify this, unless the clutch is slipping, your RPM in the same gear will always result in the same speed, you cannot change the gearing of the system. However with the A/C engaged, the amount of throttle input required to maintain that RPM will be greater than if not engaged. Much like when driving up a hill.Up!_to_Mii said:Thinking about it, surely the bog standard Up! would be slightly more relaxing as the engine won't have the a/c unit to cope with, meaning slightly lower revs at any given speed?
To clarify this further for a newbie like me, by A/C you mean the compressor used for cooling and demoisturizing? Am I right in thinking that, opposed to that, heating uses engine's waste heat and therefore doesn't increase fuel consumption? (Not counting here power needed to run fans and various electrically heated things.)shakotanVIP said:There is a lot of drag on the pulley system when the A/C pump is engaged, hence more power is required from the engine to turn at the same speed. It is widely known that having the A/C running will decrease your MPG by up to 10%.
Only when the A/C pump clutch is engaged though, it will make minimal difference if the A/C is switched off, as the pump pulley is in free-wheel.
ptae2000e said:To clarify this further for a newbie like me, by A/C you mean the compressor used for cooling and demoisturizing? Am I right in thinking that, opposed to that, heating uses engine's waste heat and therefore doesn't increase fuel consumption? (Not counting here power needed to run fans and various electrically heated things.)shakotanVIP said:There is a lot of drag on the pulley system when the A/C pump is engaged, hence more power is required from the engine to turn at the same speed. It is widely known that having the A/C running will decrease your MPG by up to 10%.
Only when the A/C pump clutch is engaged though, it will make minimal difference if the A/C is switched off, as the pump pulley is in free-wheel.