Advice for a long drive

[greendwarf]

Also the cruise control if you're using it.

I've noticed that mine is much more aggressive on the pedals than me, and results in a less smooth ride.

I take it are referring to Auto CC, where you can anticipate traffic conditions further ahead than the radar. In normal CC, I find the reverse, with the car noticing changes of gradient more quickly than me, giving a more economical consumption.

 

[ThudnBlundr]

I use the Adaptive CC on our 4hs on long journeys. But I do find that I can spot a reason to slow down far sooner than it can, as it reacts only to the car in front whereas the Mk2 eyeball can see a problem brewing much further ahead. Then the annoyance is that it's set back to 'D' (B2) when you cancel ACC, meaning I always have to flip it back up to B5 just in case. If only it remembered previous settings - not just this, but across the board. Mind you, my 2015 model doesn't turn on the brake lights unless the brake pedal is pressed, so I often press it anyway so that the people behind wake up, sorry can see that something's happening ahead

 

[mellobob]

So, is there a 1 to 1 relationship between the engine speed and the car speed? Or is there a "transmission" in the front axle which converts engine RPM to wheel power?

 

[ChrisMiller]

Also the cruise control if you're using it.

I've noticed that mine is much more aggressive on the pedals than me, and results in a less smooth ride.

Yes, I feel the same (mine has the basic cruise control, not ACC). For instance, if I've got the cruise control set for a 30mph limit and am approaching a speed restriction, travelling at 50 mph, if I then lift off and resume the cruise control, it will let the speed drop to a few mph below the set speed and then 'boot' the accelerator - sometimes to the point where the ICE will start. I'd have thought it would be almost trivial to program a smooth transition, but apparently not.

Sorry to derail the thread.

 

[greendwarf]

Then the annoyance is that it's set back to 'D' (B2) when you cancel ACC, meaning I always have to flip it back up to B5 just in case.

That's odd. I'm sure in normal CC turning it off drops back to where I have set it after turning it on. Yes, when you turn it on it sets as B2 but you can increase it up to B5. This enables me to largely dispense with both pedals under CC by just using the steering wheel controls.

 

[ThudnBlundr]

That's odd. I'm sure in normal CC turning it off drops back to where I have set it after turning it on. Yes, when you turn it on it sets as B2 but you can increase it up to B5. This enables me to largely dispense with both pedals under CC by just using the steering wheel controls.

It might be because ACC uses variable regen to control the speed before it uses the brakes.

 

[greendwarf]

That's odd. I'm sure in normal CC turning it off drops back to where I have set it after turning it on. Yes, when you turn it on it sets as B2 but you can increase it up to B5. This enables me to largely dispense with both pedals under CC by just using the steering wheel controls.

It might be because ACC uses variable regen to control the speed before it uses the brakes.

Aah! - another advantage of being back here in steerage with my Gx3h :lol:

 

[littlescrote]

So, is there a 1 to 1 relationship between the engine speed and the car speed? Or is there a "transmission" in the front axle which converts engine RPM to wheel power?

Once in parallel mode (orange arrow between engine and wheels) there is a fixed direct relationship between engine speed and car speed. It's not 1:1 as 4000rpm at the engine would result in 4000rpm at a wheel with a diameter of 225/55 which has a circumference of 80.8 inches which gives 323,520 inches per minute, or 0.08 miles per hour.

 

[kpetrov]

So, is there a 1 to 1 relationship between the engine speed and the car speed? Or is there a "transmission" in the front axle which converts engine RPM to wheel power?

Once in parallel mode (orange arrow between engine and wheels) there is a fixed direct relationship between engine speed and car speed. It's not 1:1 as 4000rpm at the engine would result in 4000rpm at a wheel with a diameter of 225/55 which has a circumference of 80.8 inches which gives 323,520 inches per minute, or 0.08 miles per hour.

Just to fix the math 4000rpm by 80.8 inches gives 323200 inches per minute or 5 miles in a minute or 300 miles per hour.
Otherwise you are right, there is an fixed ratio in the front axle and differential. Total of 3.425 reduction.

 

[user 3575]

87.59 mph

 

[zzcoopej]

87.59 mph

Phew, strange things happen to the flux capacitor if you hit 88mph !!! :lol:

 

[littlescrote]

Just to fix the math 4000rpm by 80.8 inches gives 323200 inches per minute or 5 miles in a minute or 300 miles per hour.
Otherwise you are right, there is an fixed ratio in the front axle and differential. Total of 3.425 reduction.

I didn't think it looked right, but knew it wouldn't be 1:1. I don't think the OP actually meant it as a 1:1 gearing, rather just a fixed relationship between engine and road speed.

 

[mellobob]

Just to fix the math 4000rpm by 80.8 inches gives 323200 inches per minute or 5 miles in a minute or 300 miles per hour.
Otherwise you are right, there is an fixed ratio in the front axle and differential. Total of 3.425 reduction.

I didn't think it looked right, but knew it wouldn't be 1:1. I don't think the OP actually meant it as a 1:1 gearing, rather just a fixed relationship between engine and road speed.

Yes, exactly. A fixed relationship is what I meant.