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Old 12th May 2021, 20:29   #11
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Originally Posted by Dorchester2 View Post
Thank you both. That makes sense and we can assume that Rover engineers issued a warning for some reason.

But I'll have another try nonetheless because in all my previous tests the problem of the unsettling acceleration in 4th gear aka the unreachable 5th one didn't hurt me. I don't remember noticing it or it's my memory which is likely failing...
I tried it tonight on my way home, also since I experiment regularly on this short route, I was hoping to compare notes on fuel economy as well as acceleration. I did not notice any difference in either, except that it did not lock up (which it wont when in sport mode), nor did it drop to coast when I switched it off when reducing speed without braking to a lower speed limit (which again in sport it wouldnt).

When using the resume function, there was no noticeable difference either in acceleration but this was only from 30-50. So it may be that in sport mode, as the revs are held for longer, it may simply be an economy issue.

Incidentally, in sport mode on the diesel, it will go into 5th - I think this is just above 70mph. In my experience, sport mode changes gear when the next gear will have something like 2 or 2,500 revs to start from, therefore maintaining torque.

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Originally Posted by bl52krz View Post
Why would you want to use cruise control when in sport mode? Defies my logic of using sport mode. Come to think of it, I have never bothered with sport mode.Kick down seems good enough for me.
I find there is a massive lag when using kickdown, worse if lockup has been activated. Sometimes this lag is dangerous (eg when merging from short slip roads), so when on one of these roads, I will flick it into sport mode, and it holds the gear and gives immediate acceleration without the 'box thinking about what it needs to do. Kickdown is still available too, but I find it rarely is needed.

You should give it a try, I think you will be impressed at the difference. When selected, if cruising particularly with lockup active, the reaction is immediate.
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Old 12th May 2021, 20:35   #12
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Originally Posted by 75driver View Post
I’ve never really understood the draw towards using cruise control.
My right foot has to go somewhere, and I’ve always felt it more comfortable to be on the pedal rather than the floor.🤔
Not that my commutes warrant cruise control anyways.🙄🙄


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I dont think our roads and journeys are long enough to warrant it here. Except perhaps going on the M1 to Dublin? I use it primarily to maintain speeds, in certain areas, especially ones with known speed traps in lol.

I also use it to play with the fuel economy at the same time, as this and my father's old Renault Megane were both better than me for fuel economy. I was better than my old X-Type though lol.
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Old 14th May 2021, 08:02   #13
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Originally Posted by clf View Post
I find there is a massive lag when using kickdown, worse if lockup has been activated. Sometimes this lag is dangerous (eg when merging from short slip roads), so when on one of these roads, I will flick it into sport mode, and it holds the gear and gives immediate acceleration without the 'box thinking about what it needs to do. Kickdown is still available too, but I find it rarely is needed.
You should give it a try, I think you will be impressed at the difference. When selected, if cruising particularly with lockup active, the reaction is immediate.
So yesterday going to my daughter's I've had another try in sport mode on the whole 50km (31 mls) journey which I hadn't used for a long while.
As everyone knows even you'd ask for cruise control, it can be activated only on request (set or resume) and de-activated when breaking or pushing on resuming. Hence I'm using the CC only on suitable portions of the journey, and not all of it like sport mode yesterday.

First of all - as you told - when pushing on 'RES' the reaction is impressive, immediate and even - if I may say so - a bit harsher than in eco mode.

But when reaching the wished speed - in my case 80km/h (50 mls) which is now the limit allowed on a large majority of roads and consequently a tad less than 2k revs - I swear that I'm back in top gear without the slightest difficulty.

Checking Torque Pro statistics on the whole journey (including the way back) it's obvious as expected that higher revs are used over 3k. With an auto box in eco mode and on 50 mls limited roads it looks nearly impossible to go faster than 3k revs but when doing a kick down.
Mind that among lots of short sections between 3k and 3.6k revs, I even went from 2350 revs at 81 km/h (50 mls) to 6410 revs at 103 km/h (64 mls) in 2 or 3 seconds! But do notice it was on a bypass limited at 110 km/h (68.35 mls)!




EDIT: in the table above consumption figures are wrong. Torque Pro can't adapt itself easily to E85.



In the end I had a fuel-up: on 128.62 mls (207 km) I fiiled 24.60 litres which gives 23.77 mpg (11.88 l/100km) which looks rather good for a V6 2.5 because with full E85 you need around 20% (TBH between 20 and 25% according car, temperature, speed and lots of parameters) more fuel. Hence it's at least the equivalent of around 28.5 mpg (9.9 l/100km) with 95E10, maybe a tad better. But my V6 2.5 is a special one with a few mods (derestricted air box, full derestricted SS exhaust line and a few other ones).




In the end TBH I don't actually need sport mode AND cruise control: CC is enough with some kicks downs when needed.
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Old 14th May 2021, 09:21   #14
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So yesterday going to my daughter's I've had another try in sport mode on the whole 50km (31 mls) journey which I hadn't used for a long while.
As everyone knows even you'd ask for cruise control, it can be activated only on request (set or resume) and de-activated when breaking or pushing on resuming. Hence I'm using the CC only on suitable portions of the journey, and not all of it like sport mode yesterday.

First of all - as you told - when pushing on 'RES' the reaction is impressive, immediate and even - if I may say so - a bit harsher than in eco mode.

But when reaching the wished speed - in my case 80km/h (50 mls) which is now the limit allowed on a large majority of roads and consequently a tad less than 2k revs - I swear that I'm back in top gear without the slightest difficulty.

Checking Torque Pro statistics on the whole journey (including the way back) it's obvious as expected that higher revs are used over 3k. With an auto box in eco mode and on 50 mls limited roads it looks nearly impossible to go faster than 3k revs but when doing a kick down.
Mind that among lots of short sections between 3k and 3.6k revs, I even went from 2350 revs at 81 km/h (50 mls) to 6410 revs at 103 km/h (64 mls) in 2 or 3 seconds! But do notice it was on a bypass limited at 110 km/h (68.35 mls)!

In the end I had a fuel-up: on 128.62 mls (207 km) I fiiled 24.60 litres which gives 23.77 mpg (11.88 l/100km) which looks rather good for a V6 2.5 because with full E85 you need around 20% (TBH between 20 and 25% according car, temperature, speed and lots of parameters) more fuel. Hence it's at least the equivalent of around 28.5 mpg (9.9 l/100km) with 95E10, maybe a tad better. But my V6 2.5 is a special one with a few mods (derestricted air box, full derestricted SS exhaust line and a few other ones).

In the end TBH I don't actually need sport mode AND cruise control: CC is enough with some kicks downs when needed.
After reading about your revs, an option may be to try accelerating hard, slam your pedal to the floor when in sport mode to see if it will red line - mine does this, but will change earlier if I accelerate more gently. This is not about 'using' it, but so that you are aware of the actually ability of the function, for future reference (I do not like red lining any car, but know that I can).

Another option to experiment with, may be to reset your gearbox - I notice a massive change initially. The car being more subdued to drive, seeming to take more effort to keep up with traffic, rather than 'cruise among it'.
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Old 14th May 2021, 09:42   #15
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After reading about your revs, an option may be to try accelerating hard, slam your pedal to the floor when in sport mode to see if it will red line - mine does this, but will change earlier if I accelerate more gently. This is not about 'using' it, but so that you are aware of the actually ability of the function, for future reference (I do not like red lining any car, but know that I can).

Another option to experiment with, may be to reset your gearbox - I notice a massive change initially. The car being more subdued to drive, seeming to take more effort to keep up with traffic, rather than 'cruise among it'.
BTW I think that I'd given a massive kick down just before reaching the 6.4k revs, the aim being to overtake the car ahead as quickly as possible. And - another afterthought - I'm not that sure I was driving on a 110km/h limited section...

But @clf how do you do to reset your gearbox?
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Old 14th May 2021, 09:57   #16
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But @clf how do you do to reset your gearbox?
remove the fuse or disconnect the battery for a few minutes. Over time it adapts to your driving style, it will also change if you change your driving style too. It is subtle over time, but noticeable after disconnecting the battery (for me anyway it is lol).
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Old 14th May 2021, 10:02   #17
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remove the fuse or disconnect the battery for a few minutes. Over time it adapts to your driving style, it will also change if you change your driving style too. It is subtle over time, but noticeable after disconnecting the battery (for me anyway it is lol).

I'd better to disconnect the fuse only because some controls may be lost if I disconnect the whole system.
So if I assume that driving mode is adaptative what may be the difference between keeping the mode as it is now or disconnecting battery or fuse?
Just a quicker way to see any change?
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Old 14th May 2021, 10:39   #18
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I'd better to disconnect the fuse only because some controls may be lost if I disconnect the whole system.
So if I assume that driving mode is adaptative what may be the difference between keeping the mode as it is now or disconnecting battery or fuse?
Just a quicker way to see any change?
it is just a quicker way and more noticeable change. It will then adapt over time to how you are driving.

In my case, I like to indulge in what I call 'christian racing'. Sometimes accelerating hard away from the traffic lights until the speed limit and then cruise. This seems to satisfy my desire to feel some power and temper any conscious or unconscious temptation to speed. After a reset, the car 'feels' sluggish for a week or so after. It is not of course, it just adapts to my style.
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Old 17th May 2021, 05:52   #19
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The Jatco box also determines throttle angle along with other factors, I’m sure I read somewhere it has a level sensor too. So if you’re going up a hill it will hold the gear for longer to aid ascent.
If you’re light footed however, the throttle angle won’t be sufficient to trigger a gear change so this may be another factor why it’s hesitating to change into 5th.

The only time I use Sport is locally as it’s far more drivable in S3 or S4 mode around small towns and villages. Also use it to stretch its legs a little bit every now and again.
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Old 17th May 2021, 08:28   #20
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Back to my last Thursday test, I must add that never ever before I had tested kick down AND sport mode!

I'm still amazed by the result: the car started like a bullet and never ever before I had overtaken so fast! For me it's mind-blowing: it was impressive. And what a noise: not that disturbing inside for such a short while but I don't know outside...

And I'm pretty sure that 2 elements have played their part: E85 and mainly the additional holes I've drilled in the bottom of the air box (and don't forget the full SS derestrictive exhaust line). I had immediately noticed the enhancement, the engine answer being far quicker after the airbox mod. Now it's absolutely immediate and the rising in turns is massive. I'm chuffed! But I should be cautious on our next journey next Tuesday: radars are spying everywhere...

Moreover I was wondering in which gear I may have been when overtaking at 101.4 km/h (63 mls - actual GPS speed) and 6410 revs.
Here is the answer (sorry, the page is in French but figures are hopefully international!):



So the answer is: 2nd gear!

But as my gearbox is automatic and then managed directly by the system, I assume that the engine will never be allowed to trespass the 6,750 revs limit exactly as it happened last Thursday: 6,410 revs.

After all provided it should not last too long, it cannot be damageable to the engine going up in the revs from time to time. Apart at that moment, it didn't go up over 3,700 revs, which is pretty decent and secure.

Last remark: it's good as well to be able to notice that both VIS motors are working so fine!
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  • This vehicle was the 1,190th 75 2.5 V6 Contemporary to be made out of 8,214
  • This vehicle was the 2,032nd 75 in Atlantic Blue Pearlescent (code: JEY) to be made out of 2,572 Atlantic Blue Pearlescent 75s
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