Improving fuel economy of bigger and smaller vehicles

[Justme]

So have I. But have you had identical cars one manual and one auto everything else the same? Because I hire cars constantly I go through more cars than most so often have identical models with small changes.
I do drive very hard. I get 36mpg out of a car that most people would return 50mpg. So perhaps it is my driving style but I do still see a difference between auto and manual but the gap has narrowed.

The mpg difference prob says more about how you drive the auto than the auto itself.

I would hazard a guess that you rev it up a fair bit to get it moving as your not getting the instant movement you would normally get with a manual as you add gas.

Lots of auto drivers over gas to get the car moving.

 

[fizzy]

The mpg difference prob says more about how you drive the auto than the auto itself.

I would hazard a guess that you rev it up a fair bit to get it moving as your not getting the instant movement you would normally get with a manual as you add gas.

Lots of auto drivers over gas to get the car moving.

Not really. I have driven many automatics. I like them but they suit some cars better than others. I will also use them in manual mode when decending steep hills etc or when towing to get engine braking. I have also driven most types of auto including cvt.

 

[Greeves246]

But have you driven a DAF44 Variomatic?

 

[fizzy]

But have you driven a DAF44 Variomatic?

Lol no!
One of the first CVTs.

 

[Robbie260]

Scammell is diesel and only gets 4MPG on a good run but then with a top speed of 29.4 MPH it ain't going anywhere fast, off road I can get it down to 1MPG if I try, but who cares, once fuel gets low simply fill it up.

What I don't get is why people buy cars they can't afford to run and then moan about MPG.

Yeah change in circumstances drastically dropped my salary so that and the fact that my fuel bill has gone up by £20 each time I visit the pumps on the space of the last two months so feeling the pinch a bit. Considering changing it but I'll have too see. Arnold Clarke has offered me nearly a grand more than what I payed for it 2 years ago.

Like the truck though so would be sorry to see it go.

 

[Greeves246]

Lol no!
One of the first CVTs.

Then you definately haven't ridden a Triumph Tina

 

[optima21]

I went to see a 3000 hp steam engine today......well thats how much it had when it was earning its keep

Ellenroad

Home of the Worlds Largest Working Steam Mill Engine

www.ellenroad.org.uk

my car is is 1992 polo GT with just under 100bhp and using digifant fuel injection

its 18 miles from where I live and I'd driven 9 miles before my engine got up to temperature, on on the way back I drove 14 miles before my engine got up to temperature. this is when the engine uses the lambda sensor to meter the fueling rather than the airflow meter and temperature ( and maps in the ecu). so until the lambda kicks in the engine is running rich at normal operating speeds. on the way back the first 5 miles are at motorway speed.

tonight I went out and my car was cold again, so I let the engine idle to get it up to operating temperature. it took 11 minutes before the lambda sensor kicked in.

so here is the question, is it better to waste fuel to get the engine up to temperature and then to save fuel as it works more efficiently, or just drive it from cold.

the engine oil only got up to 70c today too.

 

[PhillipM]

Drive from cold. It will take ages to warm parts through properly idling with no load, and cold idling is hell on the engine in terms of wear and tear.

 

[octo0072000]

I went to see a 3000 hp steam engine today......well thats how much it had when it was earning its keep

Ellenroad

Home of the Worlds Largest Working Steam Mill Engine

www.ellenroad.org.uk

my car is is 1992 polo GT with just under 100bhp and using digifant fuel injection

its 18 miles from where I live and I'd driven 9 miles before my engine got up to temperature, on on the way back I drove 14 miles before my engine got up to temperature. this is when the engine uses the lambda sensor to meter the fueling rather than the airflow meter and temperature ( and maps in the ecu). so until the lambda kicks in the engine is running rich at normal operating speeds. on the way back the first 5 miles are at motorway speed.

tonight I went out and my car was cold again, so I let the engine idle to get it up to operating temperature. it took 11 minutes before the lambda sensor kicked in.

so here is the question, is it better to waste fuel to get the engine up to temperature and then to save fuel as it works more efficiently, or just drive it from cold.

the engine oil only got up to 70c today too.

if it takes 9 miles to get to temp i would be changing the thermostat first then blanking off half the radiator my avensis has half the rad blocked off all year still takes about 2 miles to get heat in the heater

 

[DAPPH]

But have you driven a DAF44 Variomatic?

I used to have one of the first imported into the UK around the early 60's ? in 1984 , it was all I could afford at the time of divorce / separation proceedings in hand .... @£ 90 from from my chiseling second hand car dealing brother in law .
It served me well for a few years till a poxy Volvo estate drive rear ended it whilst I was stopped hand brake on at a pedestrian crossing on a down hill slope writing it off for £14 scrap value only ..... BTD Volvo drivers , . his repair bill was many many times that .

 

[Cobbler]

But have you driven a DAF44 Variomatic?

Someone I worked with back in the 60’s had a Daf 33, travelled as passenger in it many times. It was fantastic in the snow as it had no diff, the varying wheel speed was taken up by the two belts. It wasn’t my cup of tea as a car, but he had lost a leg in a motorcycle accident & was only able to drive an automatic & the Daf was about all that was available as a small vehicle.

 

[Blobber]

Many years ago someone I knew had one of those DAF varioamatics, he used to take hoards of kids out to various kid things and took all the seats out apart from the drivers seat to get all the kids in!

 

[julianthegypsy]

Didn't someone come out with a similar idea but with a multiplex chain or something? Variable speed belts are brilliant, I've used them on combine harvesters, for changing drum speed, my old raglan milling machine used one, as did their lathe, and my old Raleigh moped had one. So simple to service and dead reliable. I almost bought a little John lathe a few weeks ago, they only wanted £400 as it had a belt problem. I'd have snapped it up but didn't have the cash lying around. I'd be willing to bet the only thing wrong with it is that they tried changing speeds while it was turned off, and you can't. Like all variable belts, you can only adjust the speed while it's running!

 

[Farside]

Didn't someone come out with a similar idea but with a multiplex chain or something?

I think that was the basis of Ford's small autoboxes for a few years. At least, I recall it being mooted, but have no direct contact with them.

 

[julianthegypsy]

I think that was the basis of Ford's small autoboxes for a few years. At least, I recall it being mooted, but have no direct contact with them.

I had it in my head that it was Ford, I'm curious to know what happened to them now, I seem to remember they touted it as the future at the time.

 

[jsf55]

ford cvt ? google foo .... https://www.richmondfordwest.com/service/cvt-vs-automatic-glen-allen-va.htm

 

[julianthegypsy]

So it's still going!
The Fendt system is another really interesting piece of work. Brilliant in tractors as you can set the transmission to maintain a constant forward speed, or constant engine revs, or a constant torque load. Superb.

 

[James1979]

So it's still going!
The Fendt system is another really interesting piece of work. Brilliant in tractors as you can set the transmission to maintain a constant forward speed, or constant engine revs, or a constant torque load. Superb.

They really are the rolls Royce of tractors. Superbly engineered

 

[redlig]

Scammell is diesel and only gets 4MPG on a good run but then with a top speed of 29.4 MPH it ain't going anywhere fast, off road I can get it down to 1MPG if I try, but who cares, once fuel gets low simply fill it up.

What I don't get is why people buy cars they can't afford to run and then moan about MPG.

probably because they really NEED a car that does 0 to 60 in 1/2 a nanosecond and a top speed of warp 99 to dolly around at the legal limit or less and average 10.6 mph in London or some other well known race track.

 

[8ob]

Checked the truck mpg on the motorway today using a pooter on the display I didnt know existed , it averages 8.7mpg but get close to a truck in front and I get 11mpg.

Bob