6th gear

[ArthurPE]

actually best economy is the highest gear, lowest rpm that supplies enough torque to maintain speed, but not enough to accelerate...

in 6th gear, on level road, mpg will be higher at 60mph than 70, and higher still at 50 and probably 40, until the engine produces insifficent torque to keep it rolling, then you slow down or shift gears...

[PetrolDave]

actually best economy is the highest gear, lowest rpm that supplies enough torque to maintain speed, but not enough to accelerate...

Well said Arthur.

[Phil3103]

Dave / Arthur

Is this something you could play around with yourself using the cruise control then? Stick the car in 6th at, say, 50mph. The DIS will then give a consumption figure. Then use the cruise control to slow the car down gradually. Presumably the consumption figure will gradually increase until you hit the point whereby there is insufficient torque to maintain speed and the mpg will start to decrease again?

[PetrolDave]

In principle yes, but you would need to find an empty piece of road that is dead flat and do it on a windless day for it to be an accurate test. For sure the mile straight at Millbrook would be too short to do it the way you suggest, but you might be able to do it with a few runs at somewhere like Bruntingthorpe.

[ArthurPE]

Dave / Arthur

Is this something you could play around with yourself using the cruise control then? Stick the car in 6th at, say, 50mph. The DIS will then give a consumption figure. Then use the cruise control to slow the car down gradually. Presumably the consumption figure will gradually increase until you hit the point whereby there is insufficient torque to maintain speed and the mpg will start to decrease again?

good observation...I've done similar and at 2000 rpm on level ground in 6th you can approach 40 mpg

I did it a bit differently...
set it at 60, cruise...observe mpg
adjust to 50, reset mpg, then cruise & observe
and so on

again, imho the beauty of these engines are the flexability
variable timing, sophistacted ignition/fuel metering and high compression

[djcevo]

I use 6th gear from 20mph to 155+mph.

This is a big, torquey engine but it still lets you know when it's unhappy enough to want you to change down.

If you genuinely use 5th gear at 20 mph I think you should have a Prius, not a lovely RS4!!! You do not buy an RS4 to be economical, nor do you have an RS4 to "potter" around in so go get yourself a Polo blue motion or something!!!!

[ArthurPE]

I use 6th gear from 20mph to 155+mph.

This is a big, torquey engine but it still lets you know when it's unhappy enough to want you to change down.

If you genuinely use 5th gear at 20 mph I think you should have a Prius, not a lovely RS4!!! You do not buy an RS4 to be economical, nor do you have an RS4 to "potter" around in so go get yourself a Polo blue motion or something!!!!

so it's YOU who is the arbitrator of how others should use the possessions they pay for...I was wondering who that was good to know
I'll file that in the circular file

I can be used in a multitude of ways in order to experience the breadth of it's abilities and versitility...
it doesn't have to be driven 10/10th's 24/7
especially on public roads...the car is faster than most roads

[PetrolDave]

If you genuinely use 5th gear at 20 mph I think you should have a Prius, not a lovely RS4!!! You do not buy an RS4 to be economical, nor do you have an RS4 to "potter" around in so go get yourself a Polo blue motion or something!!!!

I don't choose to be stuck in traffic queues during the rush hours on my way to and from work, but like most of us I have to work to pay the bills.

When you're stuck in a traffic queue it makes no difference whether you have a Prius, a Polo Bluemotion, an RS4 or even a Bugatti Veyron - you all go at the same slow crawl. So when stuck in such a queue I might as well take advantage of the sheer torque of the RS4 engine and not have to work the clutch all the time.

As I said in an earlier post, when the queues clear and the speed limits lift - it's time for me to change down and listen to that wonderful V8 sing as it revs to 8000+rpm... and watch the Prius and Polo Bluemotion become tiny dots behind me.

BTW have you ever driven a Polo Bluemotion? I had one as a loan car a couple of months ago, and I have to say it is possibly the nastiest car I have driven in a long time. The engine is unbelieveably raucous, had a ridiculously narrow power band and only offers barely acceptable performance if you "drive it like you stole it". My wifes 1.2 Fabia HTP is a MUCH better drive (and more economical in the real world - I got 30mpg from the Polo Bluemotion and I get 45mpg from her Fabia).

[reevesroadster]

Well,

I went out and drove in 6th at low revs - it does work. 6th to 3rd takes a bit of getting used to!!!!

As Ive just got a company fuel card I think I'll stick to driving it like I stole it.........