On 21/08/15 13:09, dennis@home wrote:
On 21/08/2015 10:50, The Natural Philosopher wrote:

However a car adjusted to run on low grade fuel either by fixed design
or automatically will still run better on better fuel.



Why?

slower fuel burn usually.
less knocky more power.


--
New Socialism consists essentially in being seen to have your heart in
the right place whilst your head is in the clouds and your hand is in
someone else's pocket.

On 21/08/2015 14:00, The Natural Philosopher wrote:
On 21/08/15 13:09, dennis@home wrote:
On 21/08/2015 10:50, The Natural Philosopher wrote:

However a car adjusted to run on low grade fuel either by fixed design
or automatically will still run better on better fuel.



Why?

slower fuel burn usually.
less knocky more power.

That is assuming the engine is set up to use that power, or had a knock
sensor to advance the engine for higher octane fuels.

Otherwise it means less power. There is really no point in burning fuel
later on the downstroke or in the exhaust.

On 21/08/2015 08:54, Andrew Mawson wrote:


Many years back, the father of my then current girl friend was adamant
that he would only use Shell, and never BP as his Rover 110 went so much
better on it. I wasn't popular when I pointed out that (at the time)
they shared a delivery fleet and the same tanker delivered both so they
were the same.

Point of the story - it's very subjective and the judgement is coloured
by preconceptions.


30+ years ago I was in digs with someone who worked at one of the
refineries in the Southampton area. His job was checking the tankers in
and out of the filling points. He stated that all the tankers in the
area, irrespective of what brand/supermarket was on the side of tank,
all filled up from the same source.


--
mailto: news {at} admac {dot] myzen {dot} co {dot} uk

On Fri, 21 Aug 2015 12:29:52 +0100, "NY" wrote:

"Bob Eager" wrote in message
...
The most amusing car I saw from BMC was the Vanden Plas - 1100! The
owners of course swore it was faster, more economical, built better,
etc...

Yes, bog-standard 1100 with VdP extras like wooden dashboard and Rolls Royce
type radiator grille. Not sure whether there was thicker carpet and deeper
padding / lumbar adjustment etc on seats.

Probably different dashboard instruments - maybe circular gauges rather than
ribbon speedo with combined fuel/temp gauges in bottom corners.

You missed out the little fold down tables in the seat backs which
were probably not intended to hold a glass of ale to save downing it
quickly but did so quite nicely, or a bottle of brown.
That's what we used em for anyway when it was my mates turn to drive
us on the regular pub crawl around the county.His was actually a 1300
and he was a well off bugger compared to the rest of us 19 - 20 year
old Herberts who had Anglias ,Minis, Vivas etc. I think his Dad had
bought it for him.
It may be considered a joke car now but when rolling up in it at a
posh hostelry it was a bit of a Q car the landord and his clientele
not having time to prepare defences before we got to the bar.

G.Harman

"Adrian" wrote in message
...
Anyway, the VdP ADO16 was never anywhere NEAR as amusing as the VdP
1500... The posh Allegro.

The Allegro was amusing just by being an Allegro. Which bozo thought of
having a square ("quartic") steering wheel, given that the whole point of a
steering wheel is that it is circular and rotates about its centre so it
feeds easily through your hands as you turn it. Any "lumps" in the circle
make this very difficult.

On 21/08/2015 08:54, Andrew Mawson wrote:
"NY" wrote in message
o.uk...

"dennis@home" wrote in message
eb.com...
On 20/08/2015 22:19, Bill Wright wrote:
An expert that I trust says that supermarket fuel isn't as good as
other
fuel. He says it's all down to the additives.

Comments?

Bill

Ask the expert what the others put in that the supermarkets don't and
you will have your answer.

Has anyone (eg a motoring organisation) done any comparisons on mpg
and general smoothness of engine (difficult to quantify the latter!)
for various brands of supermarket fuel versus various brands from
named fuel chains (Jet, Esso, Shell, Texaco etc)?

The only time I've noticed a slightly smoother engine (though no
significant improvement in mpg) was when I accidently filled up with
premium diesel instead of standard diesel - and a lot of that may have
been wishful thinking to compensate for paying through the nose for
the "gold plated" fuel :-) I wouldn't have minded quite so much but
I'd driven past loads of garages on my journey, holding out for the
cheapest garage that I happened to pass, and then when I found a cheap
garage I went and used the premium holster instead of the standard
one. Shame they aren't different colours (eg black versus black with
yellow stripes, or something like that).

Many years back, the father of my then current girl friend was adamant
that he would only use Shell, and never BP as his Rover 110 went so much
better on it. I wasn't popular when I pointed out that (at the time)
they shared a delivery fleet and the same tanker delivered both so they
were the same.

That's not necessarily strictly true; tankers normally have several
compartments. Nevertheless, I agree that the non-premium products might
very well be the same.


Point of the story - it's very subjective and the judgement is coloured
by preconceptions.

Andrew

On 21/08/2015 13:29, Martin Brown wrote:
On 21/08/2015 13:08, Rod Speed wrote:


"Brian-Gaff" wrote in message
...
I heard a talking head the other day saying that as supermarket fuel
is bought on something called the spot market, it can vary, and is
often quite old and thus its octane value can be depleted.

Perhaps someone can tell me how old fuel loses its octane value?

The more volatile components evaporate off faster.

It isn't just that. Many modern fuel mixes are slightly hygroscopic and
once there is some water in it various esters can form. The upshot is
that old fuel does not evaporate to leave absolutely no residue.

The ethanol content is particularly problematic in this respect.

Storage of fuel surely has to be nailed by now.

It isn't necessarily economically viable to store
it like that with the cheapest spot market crap.

Even with stabilisers longer term you would need to keep it sealed under
nitrogen to prevent gradual slow oxidation of certain components -
especially when stored in a rusty steel tank.

Most of the stuff you find on the web about long term fuel storage is
written by deranged survivalists who are nutty as fruit cakes.


Well put!

On 21/08/2015 10:52, Nightjar cpb wrote:
On 20/08/2015 22:19, Bill Wright wrote:
An expert that I trust says that supermarket fuel isn't as good as other
fuel. He says it's all down to the additives.

This article gives as good an answer as any:

http://www.simplemotoring.co.uk/supe...branded-fuels/


Agreed, a very good link.

On 21/08/15 14:50, Fredxxx wrote:
On 21/08/2015 14:00, The Natural Philosopher wrote:
On 21/08/15 13:09, dennis@home wrote:
On 21/08/2015 10:50, The Natural Philosopher wrote:

However a car adjusted to run on low grade fuel either by fixed design
or automatically will still run better on better fuel.



Why?

slower fuel burn usually.
less knocky more power.

That is assuming the engine is set up to use that power, or had a knock
sensor to advance the engine for higher octane fuels.

No. it doesn't mean that
Go and read up on IC engine theory

Otherwise it means less power. There is really no point in burning fuel
later on the downstroke or in the exhaust.


--
New Socialism consists essentially in being seen to have your heart in
the right place whilst your head is in the clouds and your hand is in
someone else's pocket.

In article ,
Fredxxx wrote:
That is assuming the engine is set up to use that power, or had a knock
sensor to advance the engine for higher octane fuels.

Generally speaking, a knock sensor only retards the ignition from the
mapped setting. And the vast majority of UK cars are mapped to run on 95
octane.

Some high performance models are mapped for 98 octane - but not many.

--
*If one synchronized swimmer drowns, do the rest have to drown too?

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
NY wrote:
"Adrian" wrote in message
...
Anyway, the VdP ADO16 was never anywhere NEAR as amusing as the VdP
1500... The posh Allegro.

The Allegro was amusing just by being an Allegro. Which bozo thought of
having a square ("quartic") steering wheel, given that the whole point
of a steering wheel is that it is circular and rotates about its centre
so it feeds easily through your hands as you turn it. Any "lumps" in
the circle make this very difficult.

Gives you more leg clearance and better view over the top. Or that's the
idea. And perhaps to look more like a racing car - after all, the Allegro
was only one step away from that.

--
*If you lived in your car, you'd be home by now *

Dave Plowman London SW
To e-mail, change noise into sound.

On 2015-08-21, alan_m wrote:

On 21/08/2015 08:54, Andrew Mawson wrote:


Many years back, the father of my then current girl friend was adamant
that he would only use Shell, and never BP as his Rover 110 went so much
better on it. I wasn't popular when I pointed out that (at the time)
they shared a delivery fleet and the same tanker delivered both so they
were the same.

Point of the story - it's very subjective and the judgement is coloured
by preconceptions.


30+ years ago I was in digs with someone who worked at one of the
refineries in the Southampton area. His job was checking the tankers in
and out of the filling points. He stated that all the tankers in the
area, irrespective of what brand/supermarket was on the side of tank,
all filled up from the same source.

Could they put the fancy additives in separately?

On 2015-08-21, newshound wrote:

On 21/08/2015 08:54, Andrew Mawson wrote:

Many years back, the father of my then current girl friend was adamant
that he would only use Shell, and never BP as his Rover 110 went so much
better on it. I wasn't popular when I pointed out that (at the time)
they shared a delivery fleet and the same tanker delivered both so they
were the same.

That's not necessarily strictly true; tankers normally have several
compartments. Nevertheless, I agree that the non-premium products might
very well be the same.

That reminds me of the sign

SEPTIC TANKS PUMPED
SWIMMING POOLS FILLED
NOT SAME TRUCK

On 21/08/2015 15:22, The Natural Philosopher wrote:
On 21/08/15 14:50, Fredxxx wrote:
On 21/08/2015 14:00, The Natural Philosopher wrote:
On 21/08/15 13:09, dennis@home wrote:
On 21/08/2015 10:50, The Natural Philosopher wrote:

However a car adjusted to run on low grade fuel either by fixed design
or automatically will still run better on better fuel.



Why?

slower fuel burn usually.
less knocky more power.

That is assuming the engine is set up to use that power, or had a knock
sensor to advance the engine for higher octane fuels.

No. it doesn't mean that
Go and read up on IC engine theory

I would suggest you read up on the differences between high and low
octane fuels.

IC theory is all very good but quite clearly you don't understand
pre-ignition and the consequences of slow burn-high octane fuels.

Next you'll be saying high octane fuels contain more energy.

"Dave Plowman (News)" wrote in message
...
In article ,
NY wrote:
"Adrian" wrote in message
...
Anyway, the VdP ADO16 was never anywhere NEAR as amusing as the VdP
1500... The posh Allegro.

The Allegro was amusing just by being an Allegro. Which bozo thought of
having a square ("quartic") steering wheel, given that the whole point
of a steering wheel is that it is circular and rotates about its centre
so it feeds easily through your hands as you turn it. Any "lumps" in
the circle make this very difficult.

Gives you more leg clearance and better view over the top. Or that's the
idea.

Very laudable - but a wheel should be *round*, dammit :-) Anyway, it's only
better leg clearance until you turn the wheel slightly and one of the lumps
bashes your thigh.

And perhaps to look more like a racing car - after all, the Allegro was
only one step away from that.

Ah yes, I was forgetting about the Allegro SRi twin-turbo V8 3.5 litre :-)

Mind you, the elastic (sorry, Hydrolastic) suspension might have limited its
road-holding on a race track :-)


I still reckon an Allegro with a Rolls Royce / Van den Plas radiator grille
looks especially absurd.

On 21/08/15 15:11, NY wrote:
"Adrian" wrote in message
...
Anyway, the VdP ADO16 was never anywhere NEAR as amusing as the VdP
1500... The posh Allegro.

The Allegro was amusing just by being an Allegro. Which bozo thought of
having a square ("quartic") steering wheel, given that the whole point
of a steering wheel is that it is circular and rotates about its centre
so it feeds easily through your hands as you turn it. Any "lumps" in the
circle make this very difficult.

The wheel og my Citroën C2 is round but mounted off-cent there is
more legroom when it is in the straight-ahead position.

On Fri, 21 Aug 2015 15:11:47 +0100
"NY" wrote:

"Adrian" wrote in message
...
Anyway, the VdP ADO16 was never anywhere NEAR as amusing as the VdP
1500... The posh Allegro.

The Allegro was amusing just by being an Allegro. Which bozo thought
of having a square ("quartic") steering wheel, given that the whole
point of a steering wheel is that it is circular and rotates about
its centre so it feeds easily through your hands as you turn it. Any
"lumps" in the circle make this very difficult.


My only experience of driving an Allegro was when I picked one up from
the company pool for a trip to Spain, back in the mid 1970s. I drove
it straight to Southampton, cruised to Balboa, then drove across
country to Valencia. Usually, half of the road was tarmac, but it
could be the left side, the right side, or the middle bit. Worked at
the new Ford Fiesta plant for a few months, then drove back to Balboa
overnight to meet the ferry leaving at 9 am, driving straight on board
without even turning off the engine. I was happy to return the Allegro
to its home. It had been reliable, though.

--
Davey.

On Fri, 21 Aug 2015 11:02:28 +0100, News
wrote:

In message , Bill Wright
writes
An expert that I trust says that supermarket fuel isn't as good as
other fuel. He says it's all down to the additives.

This argument has been going on as long as I have been buying petrol
(mid 60s), and doubtless a lot longer. Don't buy cheap brands - they're
made from the dregs at the bottom of the tanker's tank.

One of mantras that used to do the rounds that was just about dying
off in the mid sixties concerned the JET brand of petrol. One of the
earliest suppliers of cheaper fuel against the established suppliers
many users believed the story that it was cheaper because the company
obtained it from left over goverment stocks of Pool petrol from WW2.

G.Harman

NY wrote:

Mind you, the elastic (sorry, Hydrolastic) suspension might have limited its
road-holding on a race track :-)

In principle hydropneumatic suspension of some sort can give excellent
roadholding. The Citroen XM is a case in point.

--
Chris Green
·

On Fri, 21 Aug 2015 02:35:40 -0700, therustyone wrote:


The only time I've noticed a slightly smoother engine (though no
significant improvement in mpg) was when I accidently filled up with
premium diesel instead of standard diesel - and a lot of that may have
been wishful thinking to compensate for paying through the nose for the
"gold plated" fuel :-) I wouldn't have minded quite so much but I'd
driven past loads of garages on my journey, holding out for the
cheapest garage that I happened to pass, and then when I found a cheap
garage I went and used the premium holster instead of the standard one.
Shame they aren't different colours (eg black versus black with yellow
stripes, or something like that).

might depend on the car's sophistication. A quality engine will monitor
pinking and adjust the timing and fuel ratio to optimise burning with
the better quality (petrol anyway) it finds. An older car will just be
set to run on the worst fuel around.

There's no need for any fancy engine management gizmos to make a car
petroleum spirit agnostic as anyone who owned a 1970s Lada (eg my dear
departed Papa) would be able to tell you.

There was an under the bonnet octane rating adjustment. Basically it
amounted to a calibrated ignition advance/retard adjustment with a
vernier thumb screw.

--
Johnny B Good

In message ,
writes
On Fri, 21 Aug 2015 11:02:28 +0100, News
wrote:

This argument has been going on as long as I have been buying petrol
(mid 60s), and doubtless a lot longer. Don't buy cheap brands - they're
made from the dregs at the bottom of the tanker's tank.

One of mantras that used to do the rounds that was just about dying
off in the mid sixties concerned the JET brand of petrol.

Yes! Jet. That was the name I was trying to remember earlier, and yes,
Jet was the subject of many a story, probably all untrue.

--
Graeme

The Natural Philosopher wrote:
On 21/08/15 10:35, therustyone wrote:


The only time I've noticed a slightly smoother engine (though no
significant improvement in mpg) was when I accidently filled up
with premium diesel instead of standard diesel - and a lot of that
may have been wishful thinking to compensate for paying through the
nose for the "gold plated" fuel :-) I wouldn't have minded quite
so much but I'd driven past loads of garages on my journey, holding
out for the cheapest garage that I happened to pass, and then when
I found a cheap garage I went and used the premium holster instead
of the standard one. Shame they aren't different colours (eg black
versus black with yellow stripes, or something like that).

might depend on the car's sophistication. A quality engine will
monitor pinking and adjust the timing and fuel ratio to optimise
burning with the better quality (petrol anyway) it finds. An older
car will just be set to run on the worst fuel around.

However a car adjusted to run on low grade fuel either by fixed design or
automatically will still run better on better fuel.


Only if it has knock sensors or other ways of detecting and actually
capitalising on the better fuel's properties. Not all cars show
improvements with premium fuels.

Tim

"NY" wrote:
"Adrian" wrote in message ...
On Fri, 21 Aug 2015 09:44:51 +0100, Brian-Gaff wrote:

Storage of fuel surely has to be nailed by now.

Quite the opposite. Modern fuel is more volatile than it used to be, and
"goes off" more quickly.

Supermarket fuel comes from the same small handful of regional
distribution depots as any other fuel. Their tanks are fed from the same
pipelines from the same tiny handful of national refineries as any other
fuel.

The ONLY difference is the almost homeopathic buckets of additive poured
into the tanker at the time of filling.

Or the non-homeopathic buckets of highly non-approved additives added by the forecourt :-(

There was a story in the local paper about 40 years ago about a garage
owner nearby who had been prosecuted for adding buckets of *water* (yes,
water!) to his forecourt petrol tanks to make the delivery go further!!!
People had been complaining that their cars misfired after filling up at
his garage. The tank was dipped and the petrol was found to be
contaminated with water. He tried to claim in court that rainwater had
been leaking into the tank - until an undercover photo was produced
showing him pouring a liquid from a bucket into the manhole of the tank...

I've no idea what size of tank this garage may have had but surely using a
bucket would take forever to make a significant difference. Why not use a
hosepipe?

Tim

Martin Brown wrote
Rod Speed wrote
Brian-Gaff wrote

I heard a talking head the other day saying that as supermarket fuel is
bought on something called the spot market, it can vary, and is often
quite old and thus its octane value can be depleted.

Perhaps someone can tell me how old fuel loses its octane value?

The more volatile components evaporate off faster.

It isn't just that. Many modern fuel mixes are slightly hygroscopic and
once there is some water in it various esters can form. The upshot is that
old fuel does not evaporate to leave absolutely no residue.

Sure, but that doesn’t affect the octane rating that much.

The ethanol content is particularly problematic in this respect.

Storage of fuel surely has to be nailed by now.

It isn't necessarily economically viable to store
it like that with the cheapest spot market crap.

Even with stabilisers longer term you would need to keep it sealed under
nitrogen to prevent gradual slow oxidation of certain components -
especially when stored in a rusty steel tank.

Yeah, that's what I meant about the economics.

No one is going to do that with the cheapest crap spot market petrol.

Most of the stuff you find on the web about long term fuel storage is
written by deranged survivalists who are nutty as fruit cakes.

Yeah, I've got some that's been in a couple of jerrycans
that I had for the camping trips in the 70s that still
works fine without anything done to it at all.

And that’s in an area where we can get 10 days in a row
over 100F, tho it doesn’t get quite that hot where the
jerrycans live.

"Bill Wright" wrote in message
...
An expert that I trust says that supermarket fuel isn't as good as
other fuel. He says it's all down to the additives.

Comments?

"alan_m" wrote in message
...
On 21/08/2015 08:54, Andrew Mawson wrote:


Many years back, the father of my then current girl friend was adamant
that he would only use Shell, and never BP as his Rover 110 went so much
better on it. I wasn't popular when I pointed out that (at the time)
they shared a delivery fleet and the same tanker delivered both so they
were the same.

Point of the story - it's very subjective and the judgement is coloured
by preconceptions.


30+ years ago I was in digs with someone who worked at one of the
refineries in the Southampton area. His job was checking the tankers in
and out of the filling points. He stated that all the tankers in the
area, irrespective of what brand/supermarket was on the side of tank, all
filled up from the same source.

Irrelevant to what they add to it before delivering it.

On 20/08/2015 22:19, Bill Wright wrote:
An expert that I trust says that supermarket fuel isn't as good as other
fuel. He says it's all down to the additives.

Comments?

It also depends on the quantity of ethanol added - particularly on older
engines.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Tim+ wrote:

"NY" wrote:

There was a story in the local paper about 40 years ago about a garage
owner nearby who had been prosecuted for adding buckets of *water* (yes,
water!) to his forecourt petrol tanks to make the delivery go further!!!

I've no idea what size of tank this garage may have had but surely using a
bucket would take forever to make a significant difference. Why not use a
hosepipe?

Back in the days of mechanical pumps there used to be a
mechanical number display on the side, which was the actual total
gallons dispensed, and a multiplication factor which was close
(but not equal) to 1.

AIUI, because the pump accuracy was greater than the tolerance
specified by Weights and Measures, it was possible to routinely
dispense slightly less than was indicated. Not much, but enough
to be worth doing.

Chris
--
Chris J Dixon Nottingham UK


Plant amazing Acers.

News wrote:

In message ,
writes

One of mantras that used to do the rounds that was just about dying
off in the mid sixties concerned the JET brand of petrol.

Yes! Jet. That was the name I was trying to remember earlier, and yes,
Jet was the subject of many a story, probably all untrue.

Back then, fuel prices seemed much less volatile, and it seemed
much easier to predict whether it would be a cheap or expensive
station by simply seeing the brand. Nowadays there really doesn't
seem to be any predictability at all.

Chris
--
Chris J Dixon Nottingham UK


Plant amazing Acers.

On Sat, 22 Aug 2015 01:29:30 +0100, John Rumm wrote:

An expert that I trust says that supermarket fuel isn't as good as
other fuel. He says it's all down to the additives.

It also depends on the quantity of ethanol added - particularly on older
engines.

You won't find any petrol that's less than 5% Ethanol, and - unless
clearly labelled E10 - it cannot be more.

On 22/08/2015 08:04, Chris J Dixon wrote:
News wrote:

In message ,
writes

One of mantras that used to do the rounds that was just about dying
off in the mid sixties concerned the JET brand of petrol.

Yes! Jet. That was the name I was trying to remember earlier, and yes,
Jet was the subject of many a story, probably all untrue.

There was also ICI petrol back then which for them was a refinery waste
stream. Only problem with it was their petrol was much smellier than
other brands but it was certainly cheaper!

Back then, fuel prices seemed much less volatile, and it seemed
much easier to predict whether it would be a cheap or expensive
station by simply seeing the brand. Nowadays there really doesn't
seem to be any predictability at all.

I dunno about that - proximity to an airport, motorway services or on a
dual carriageway pretty much guarantees spot price + 5p.

It is also a lot more expensive in the hills and dales where just
getting the stuff delivered in bulk adds significant extra costs.

It used to be cheaper near major refineries too but I no longer live
close enough to one to check this these days.

--
Regards,
Martin Brown

In article ,
Martin Brown wrote:
On 22/08/2015 08:04, Chris J Dixon wrote:
News wrote:

In message ,
writes

One of mantras that used to do the rounds that was just about dying
off in the mid sixties concerned the JET brand of petrol.

Yes! Jet. That was the name I was trying to remember earlier, and yes,
Jet was the subject of many a story, probably all untrue.

There was also ICI petrol back then which for them was a refinery waste
stream. Only problem with it was their petrol was much smellier than
other brands but it was certainly cheaper!

Back then, fuel prices seemed much less volatile, and it seemed
much easier to predict whether it would be a cheap or expensive
station by simply seeing the brand. Nowadays there really doesn't
seem to be any predictability at all.

I dunno about that - proximity to an airport, motorway services or on a
dual carriageway pretty much guarantees spot price + 5p.

Nearer 10p.

It is also a lot more expensive in the hills and dales where just
getting the stuff delivered in bulk adds significant extra costs.

In the 1950 we holidayed a remote village in Scotland where the petrol
arrived on the "steamer" in 50 gal drums. The deposit on the drums was
less taht the cost of sending them back - so they ended up in the sea. The
cost of the petrol had to allow for this. There was a road, but it was
narrow and 3ply. The tanker drivers refused to use it, which is why petrol
(and presumably TVO) had to come by sea.

On 21/08/15 20:44, wrote:
NY wrote:

Mind you, the elastic (sorry, Hydrolastic) suspension might have limited its
road-holding on a race track :-)

In principle hydropneumatic suspension of some sort can give excellent
roadholding. The Citroen XM is a case in point.


Its not the technology, its how its actually implemented

the diagonal coupling between wheels made the austin 1100 handling
'interesting' to say the least.

But it was quite a smooth ride.


--
New Socialism consists essentially in being seen to have your heart in
the right place whilst your head is in the clouds and your hand is in
someone else's pocket.

On 21/08/15 23:22, Tim+ wrote:
The Natural Philosopher wrote:
On 21/08/15 10:35, therustyone wrote:


The only time I've noticed a slightly smoother engine (though no
significant improvement in mpg) was when I accidently filled up
with premium diesel instead of standard diesel - and a lot of that
may have been wishful thinking to compensate for paying through the
nose for the "gold plated" fuel :-) I wouldn't have minded quite
so much but I'd driven past loads of garages on my journey, holding
out for the cheapest garage that I happened to pass, and then when
I found a cheap garage I went and used the premium holster instead
of the standard one. Shame they aren't different colours (eg black
versus black with yellow stripes, or something like that).

might depend on the car's sophistication. A quality engine will
monitor pinking and adjust the timing and fuel ratio to optimise
burning with the better quality (petrol anyway) it finds. An older
car will just be set to run on the worst fuel around.

However a car adjusted to run on low grade fuel either by fixed design or
automatically will still run better on better fuel.


Only if it has knock sensors or other ways of detecting and actually
capitalising on the better fuel's properties. Not all cars show
improvements with premium fuels.

You still don't get it do you?

There is a world of difference between 'runs acceptably without damage'
and 'best power output/smoothest running/best economy'


To take an extreme example. IF you add - say - nitromethane to your
tank, you will without any retunes at all get a massive power increase.

Simply because its an oxidiser. it adds oxygen to the mix. So where a
conventional engine might run out of breath the nitro engine will keep
going to higher revs.

The shape of the bang - not just its timing - makes a real difference to
power output and fuel economy.

All IC engines ignite before top dead centre, so a sharp bang then
actually slows the piston down. You will optimise to get MOST of the
ignition pressure after top dead centre where it does the most good, but
automagically adjusting the ignition timing can only compensate so far.

A short sharp bang is not as efficacious as a longer slower one.

However the fuel mix and timing is only part of the story - the engine
designer has compressions ratios, turbo boosting and combustion chamber
shape to play with to affect the ignition explosion character.

And with direct injection these days, the injection can be more than
once per combustion.


The final point being the engine is designed and mapped for one
particular grade of fuel. And tested to ensure that others don't cause
problems, but it is not optimised for them. All cars will run best on a
particular grade and better or worse on others. And the RON number means
nithg8ingm as any F1 aficionado will tell you. F1 fuel at one time was
restricted to some RON number, but that didn't stop them putting in all
manner of additives to constrict a highly toxic witches brew that gave a
huge amount more power than 'pump fuel' of the same RON number would
have dopne.


And that is why you get such widely varying reports as 'my car runs best
on X' or 'my car ran worse on X' or 'my car runs the same on all grades'

Having a misspent youth tuning up small sports cars, I am particularly
sensitive. One time I had a distinct vibration in my latest vehicle, a
sort of engine thrumming at 70mph+. After refilling it at a different
station, that disappeared.

Mind you the fuel pump was failing and did fail nearly completely some
few hundred miles later, which may have been a contributory factor.



Basically if you actually care at all, try every single brand of fuel
you can, and test them against YOUR car and YOUR driving style, and
realise that its *more* likely that you will get a predictable fuel
grade from a branded station than a supermarket.

Otherwise accept that if you fill up where its cheap, you *may* get
reduced performance and shorter engine life on some or other components.
Or you may not. It depends.

If you are driving a mass produced shopping trolley with 'tesco rash'
dents everywhere that you will scrap at 100k miles anyway, well fine.


Tim



--
New Socialism consists essentially in being seen to have your heart in
the right place whilst your head is in the clouds and your hand is in
someone else's pocket.

On 22/08/15 07:57, Chris J Dixon wrote:
Tim+ wrote:

"NY" wrote:

There was a story in the local paper about 40 years ago about a garage
owner nearby who had been prosecuted for adding buckets of *water* (yes,
water!) to his forecourt petrol tanks to make the delivery go further!!!

I've no idea what size of tank this garage may have had but surely using a
bucket would take forever to make a significant difference. Why not use a
hosepipe?

Back in the days of mechanical pumps there used to be a
mechanical number display on the side, which was the actual total
gallons dispensed, and a multiplication factor which was close
(but not equal) to 1.

AIUI, because the pump accuracy was greater than the tolerance
specified by Weights and Measures, it was possible to routinely
dispense slightly less than was indicated. Not much, but enough
to be worth doing.


It still; is. Nearly all my refills exceed the 'total tank capacity' by
quite a large margin.

In tease days of fuel filters I refill on a warning ligh + 40 miles.. :-)


Chris



--
New Socialism consists essentially in being seen to have your heart in
the right place whilst your head is in the clouds and your hand is in
someone else's pocket.

On 22/08/15 10:35, Huge wrote:
On 2015-08-21, therustyone wrote:


The only time I've noticed a slightly smoother engine (though no
significant improvement in mpg) was when I accidently filled up
with premium diesel instead of standard diesel - and a lot of
that may have been wishful thinking to compensate for paying
through the nose for the "gold plated" fuel :-) I wouldn't have
minded quite so much but I'd driven past loads of garages on my
journey, holding out for the cheapest garage that I happened to
pass, and then when I found a cheap garage I went and used the
premium holster instead of the standard one. Shame they aren't
different colours (eg black versus black with yellow stripes, or
something like that).

might depend on the car's sophistication. A quality engine will
monitor pinking and adjust the timing

Diesels don't pink and have no ignition timing.

Wrong on both counts. Why am I not surprised?

Diesel 'clatter' IS pinking.. today's direct injection diesels vary the
timing as part of the fuel mapping - when you inject is largely when it
fires. And multiple injects per cycle can be done - that really helps
with the low speed 'clatter'

http://papers.sae.org/2008-01-1329/

I also have severe doubts that premium diesel achieves anything
whatsoever other than increasing the profits of the oil companies.


That's as may be, but there are definite issues with using some grades
of diesel in some diesel engines.

In particular biodiesel can lead to gumming of injectors and corrosion
of seals and fuel pump and injector parts, and diesel that doesn't have
additives may fail to absorb water and leave that at the bottom of the
tank, or freeze up badly in winter.

'City Diesel' was designed for vehicles that do stop start type motoring
and also IIRC features very low sulphur levels.

Marketing bollox is not all lies. Usually there is a grain of truth at
the bottom.






--
New Socialism consists essentially in being seen to have your heart in
the right place whilst your head is in the clouds and your hand is in
someone else's pocket.

On 22/08/15 10:58, Huge wrote:
On 2015-08-21, Martin Brown
wrote:
On 20/08/2015 22:19, Bill Wright wrote:

An expert that I trust says that supermarket fuel isn't as good
as other fuel. He says it's all down to the additives.

Comments?

There are tiny differences in the additive packages with the
supermarkets cutting corners a bit but all the fuel is to the
British standard and only the tetchiest of engines will see any
difference.

It really only matters when they put the entirely the wrong
additive package in as happened in 2007 and again in 2014 to a
lesser extent.

https://en.wikipedia.org/wiki/2007_U..._contamination



Petrol engines really don't like the *diesel* additive package.

FWIW I am happy to buy supermarket fuel at the best price I can
get.

You and me both. And always have. Even in performance vehicles.
There is an astonishing amount of cock spouted about this, especially
given the subjectivity of people assessing their own fuel choices.


I have no particular axe to grind, but even I find your total ignorance
astounding. Fuel is not a single item. It is a blend of stuff including
unwanted things like water, that has a definite and measurable impact on
car engine performance.

All fuels are not created equal, that is established fact.

What is less definite is which fuels, if any, are reliably better, and
in what way.




--
New Socialism consists essentially in being seen to have your heart in
the right place whilst your head is in the clouds and your hand is in
someone else's pocket.

Chris J Dixon wrote:

Back in the days of mechanical pumps there used to be a mechanical
number display on the side, which was the actual total gallons
dispensed

There still are, you can gauge the relative volumes of unleaded, diesel,
and "super" variations sold while you fill-up.

En el artículo , Huge
escribió:

Diesels don't pink and have no ignition timing. I also have severe doubts that
premium diesel achieves anything whatsoever other than increasing the profits of
the oil companies.

They claim it has increased lubricity and doesn't wax up as easily in
very cold weather. No particular axe to grind, just saying that's how
they justify the higher price.

Side note: diesel prices are on a par with petrol in the local filling
stations, allegedly because of over-supply.

--
(\_/)
(='.'=) Bunny says: Windows 10? Nein danke!
(")_(")

In article ,
NY wrote:
Mind you, the elastic (sorry, Hydrolastic) suspension might have limited
its road-holding on a race track :-)

The Allegro - in good condition - handled very well. Much better than many
of the conventionally sprung cars of the day.

--
*It's a thankless job, but I've got a lot of Karma to burn off

Dave Plowman London SW
To e-mail, change noise into sound.

On 22/08/2015 11:11, Mike Tomlinson wrote:
En el artículo , Huge
escribió:

Diesels don't pink and have no ignition timing. I also have severe doubts that
premium diesel achieves anything whatsoever other than increasing the profits of
the oil companies.

They claim it has increased lubricity and doesn't wax up as easily in
very cold weather. No particular axe to grind, just saying that's how
they justify the higher price.

Side note: diesel prices are on a par with petrol in the local filling
stations, allegedly because of over-supply.

Given that cracking a gallon of petrol takes a pint of oil, one can see
why petrol should be more than diesel.

Shame the additional fuel usage for cracking isn't included on the CO2
per mile figures.