Is your Tiv pinking?
Discussion
A friend sent me this email, I thought it might be of interest.......only what we all suspected but it's interesting to see it spelled out
Found this on the Cupra website, quite interesting:
"I work with petrol companies, so I'll let you into some lesser known secrets.
Super unleaded is a fine fuel, but only if purchased from reputable dealers. Esso SUPER, like BP are about the best you can buy. Supermarket stuff is just 4 star without the valve addictive, which itself is just 95 unleaded that has been octane boosted. AVOID AT ALL COSTS. Supermarket petrol is a very dirty fuel. Any engineer of their pumps will confirm that.
I have seen the results of their filters and you get everything from feathers to god knows what flowing through supermarket fuels. EVEN SAND.
All Super by law has to be 97 ron, but where its stable enough to hold higher octane, stations are able to advertise its octane as being higher sometimes.
Optimax has a variable octane rating, due to its structure its less stable, but leaves the refinery at 101 octane.
That's the equivalent to the old 5 star for those old enough to remember it.
By the time you buy it, its closer to around 97.
This is why its octane isn't always stated.
Normal 95 or 97 fuels wont lose octane, whereas optimax does, but used fresh, its the highest octane fuel you can buy.
All supermarket fuels come from either the Matex or Purfleit refineries for the south east. These only take oil from the eastern block. They are most definitely NOT the same fuels as ESSO and such like.
They also remix contaminations for other companies then sell the fuel on via supermarkets as well.
On average, each 50 litres brought from a supermarket will have 8% contaminates, and 9 grams of grit.
I have got 2 test tubes sitting on my desk at work of both ESSO and Tesco regular 95 for simple comparisons when arguing these points with supermarket buyers.
There is a bead in both which on the Tesco tube floats in mid suspension due to the grittiness of its petrol.
The ESSO falls straight to the bottom.
These are random samples taken every few weeks, and the results are always the same.
Texaco is a subsidiary of ESSO and both use the same petrol.
There are basically 3 companies which supply fuel to the UK. ESSO, BP, AND SHELL.
Each sells to all the other names you find.
JET, FINA, Q8 and a few other smaller outlets all use SHELL.
TEXACO and TOTAL use ESSO,
Supermarkets use Eastern Block fuels, which are primarily designed for the 91 Ron continent market.
These are upgraded in the UK to UK specs by using Butane gas.
Hence to avoid.
BP Ultimate is just its old Super grade cleaned up a bit.
I.E.. It goes through another filter at the refinery.
Not a bad fuel though, second only to ESSO in quality.
Its Diesel is the best in the world for all you Diesel owners.
OPTICRAP. Need I say more. All grades supplied by Shell.
Might as well fill from your local FINA station and pop a bottle of Halfarts octane super duper booster plus in.
ESSO 95 and 97 = If you want every pennies worth in quality petrol, look no further.
Get it at your local TOTAL, TEXACO or ESSO now
Found this on the Cupra website, quite interesting:
"I work with petrol companies, so I'll let you into some lesser known secrets.
Super unleaded is a fine fuel, but only if purchased from reputable dealers. Esso SUPER, like BP are about the best you can buy. Supermarket stuff is just 4 star without the valve addictive, which itself is just 95 unleaded that has been octane boosted. AVOID AT ALL COSTS. Supermarket petrol is a very dirty fuel. Any engineer of their pumps will confirm that.
I have seen the results of their filters and you get everything from feathers to god knows what flowing through supermarket fuels. EVEN SAND.
All Super by law has to be 97 ron, but where its stable enough to hold higher octane, stations are able to advertise its octane as being higher sometimes.
Optimax has a variable octane rating, due to its structure its less stable, but leaves the refinery at 101 octane.
That's the equivalent to the old 5 star for those old enough to remember it.
By the time you buy it, its closer to around 97.
This is why its octane isn't always stated.
Normal 95 or 97 fuels wont lose octane, whereas optimax does, but used fresh, its the highest octane fuel you can buy.
All supermarket fuels come from either the Matex or Purfleit refineries for the south east. These only take oil from the eastern block. They are most definitely NOT the same fuels as ESSO and such like.
They also remix contaminations for other companies then sell the fuel on via supermarkets as well.
On average, each 50 litres brought from a supermarket will have 8% contaminates, and 9 grams of grit.
I have got 2 test tubes sitting on my desk at work of both ESSO and Tesco regular 95 for simple comparisons when arguing these points with supermarket buyers.
There is a bead in both which on the Tesco tube floats in mid suspension due to the grittiness of its petrol.
The ESSO falls straight to the bottom.
These are random samples taken every few weeks, and the results are always the same.
Texaco is a subsidiary of ESSO and both use the same petrol.
There are basically 3 companies which supply fuel to the UK. ESSO, BP, AND SHELL.
Each sells to all the other names you find.
JET, FINA, Q8 and a few other smaller outlets all use SHELL.
TEXACO and TOTAL use ESSO,
Supermarkets use Eastern Block fuels, which are primarily designed for the 91 Ron continent market.
These are upgraded in the UK to UK specs by using Butane gas.
Hence to avoid.
BP Ultimate is just its old Super grade cleaned up a bit.
I.E.. It goes through another filter at the refinery.
Not a bad fuel though, second only to ESSO in quality.
Its Diesel is the best in the world for all you Diesel owners.
OPTICRAP. Need I say more. All grades supplied by Shell.
Might as well fill from your local FINA station and pop a bottle of Halfarts octane super duper booster plus in.
ESSO 95 and 97 = If you want every pennies worth in quality petrol, look no further.
Get it at your local TOTAL, TEXACO or ESSO now
Right, so from now on I use Esso for super-unleaded only?
But surely, if you've got a twin fuel line filter system no grit should get through?
Hmmmm.....
Sounds wierd to me... like Esso funded biased info me thinks....
Right, this weekend, I will go to an Esso, Shell, BP and a Tescos station and get some fuel from each.
I will then particle analyse it, and run it through a chemical composition breakdown... and run some molecular reaction tests at engine combustion temperatures... and also run it through accelerated aging tests to compare the molecular bonds of the octane...
or...
in the real world, I will stick to using BP Ultimate.
But surely, if you've got a twin fuel line filter system no grit should get through?
Hmmmm.....
Sounds wierd to me... like Esso funded biased info me thinks....
Right, this weekend, I will go to an Esso, Shell, BP and a Tescos station and get some fuel from each.
I will then particle analyse it, and run it through a chemical composition breakdown... and run some molecular reaction tests at engine combustion temperatures... and also run it through accelerated aging tests to compare the molecular bonds of the octane...
or...
in the real world, I will stick to using BP Ultimate.
As has repeatedly been pointed out, the original post is unmitigated piffle. (And, BTW, I've been running my cars on supermarket fuel for decades without any problems whatsoever.)
There is a *very* comprehensive FAQ about fuel here;
www.faqs.org/faqs/autos/gasoline-faq/part1/
There is a *very* comprehensive FAQ about fuel here;
www.faqs.org/faqs/autos/gasoline-faq/part1/
I was told the same by friends at Shell and BP. I trialled running my old Land Rover on Asda fuel for 2 months, then Shell fuel. Car was serviced at the end of both trials. The one thing I noticed was that the car did run better on the Shell fuel and was cleaner.
Since then I've never used supermarket fuel and have had less issues with injectors and filters.
Maybe there is something in it afterall
Since then I've never used supermarket fuel and have had less issues with injectors and filters.
Maybe there is something in it afterall
No1 son works, as a poor student, doing shifts in Sainsbury's petrol station to collect his beer tokens. He assures me the deliveries are always BP drivers and but not always BP liveried lorries, sometimes they are but it is not encouraged 
. As a junior petrol head himself (maxed 306 thingy) he has asked the delivery chaps whats different, answer always is 'its the same lorry load whether its sainsbury's or BP'.
Doesn't stop me topping up there
, saves myself a small fortune every time 
, particularly when you subtract the 5p/ltr voucher you get with the shopping . Harry
While the original poster may be spinning the story a little I do think there is some truth in the OPTIMAX comment.
I have been very disappointed in the variable quality of OPTIMAX where I live. To the point that I have had some pinking running on some garages OPTIMAX. I have a Chim 500.
My assumptions have been that either the garage has mixed fuels 95 and 97 in the OPTIMAX tank or in fact ripped me off selling me 95 instead of OPTIMAX. So, if OPTIMAX is unstable then it would explain the variability I have seen in the performance of the Chim. 95 is way more popular than any of the 97 fuels so it will hang around in a tank much longer than 95.
However, the OPTIMAX question is of no concern now as I had the car serviced at TOPCATS and they obviously recognised the pinking and adjusted the timing. Lost a bit of power but better than running the risk with pinking.
I have run the car on BP Ultimate and noticed little difference to OPTIMAX. Never tried Esso super but may well give it a go.
Thinking about the accusation of spin once more leads me to think that we could all be guilty of the same charge. Very few of us are petrochemical engineers but we will if asked tell the story of OPTIMAX being the best fuel to run a TVR. This being based on nothing more than advice from this forum. I know that I have been biased in this way and I am a "card carrying" scientist who should know better than to accept dogma without supporting experimentation and evidence.
I have been very disappointed in the variable quality of OPTIMAX where I live. To the point that I have had some pinking running on some garages OPTIMAX. I have a Chim 500.
My assumptions have been that either the garage has mixed fuels 95 and 97 in the OPTIMAX tank or in fact ripped me off selling me 95 instead of OPTIMAX. So, if OPTIMAX is unstable then it would explain the variability I have seen in the performance of the Chim. 95 is way more popular than any of the 97 fuels so it will hang around in a tank much longer than 95.
However, the OPTIMAX question is of no concern now as I had the car serviced at TOPCATS and they obviously recognised the pinking and adjusted the timing. Lost a bit of power but better than running the risk with pinking.
I have run the car on BP Ultimate and noticed little difference to OPTIMAX. Never tried Esso super but may well give it a go.
Thinking about the accusation of spin once more leads me to think that we could all be guilty of the same charge. Very few of us are petrochemical engineers but we will if asked tell the story of OPTIMAX being the best fuel to run a TVR. This being based on nothing more than advice from this forum. I know that I have been biased in this way and I am a "card carrying" scientist who should know better than to accept dogma without supporting experimentation and evidence.
bennem said:
Very few of us are petrochemical engineers but we will if asked tell the story of OPTIMAX being the best fuel to run a TVR. This being based on nothing more than advice from this forum.
I disagree. We say Optimax because until recently it was the highest octane unleaded fuel available
surely the state of the forecourt's petrol tank's
make's all the difference, when were they last cleaned out, think of all that water that sits in the bottom of the tank with all the other crap mixed in.
a friend used to do forecourt maintenance and he told me water in the tanks is a common problem
make's all the difference, when were they last cleaned out, think of all that water that sits in the bottom of the tank with all the other crap mixed in.
a friend used to do forecourt maintenance and he told me water in the tanks is a common problem
I have never read so much unmitigated cobblers....I work in the UK for the largest refiner in the USA at one of its oil refineries, the companies mentioned are far from the only ones selling petrol in the UK. My company OWNs JET . As I have stated before in other threads ... supermarket petrol is EXACTLY the same as any other. FACT. Quite a few stations such as the SAVE group don't own any refineries so buy their petrol at the best price they can from the Rodderdam spot market so could come from anywhere in the world. Our refinery supplies JET, esso, texaco and many others but most of our output ( 1 million gallons a day of unleaded ) goes to the US. I wish people would get their facts from somewhere other than the pub toilet expert...
Well said Snorky! I've been using Sainsbury's super unleaded recently, since it's only 2p dearer than regular unleaded (the one in Cobham just off the A3 for those in Surrey), not noticed any problemsor indeed any difference.
All this unfounded scare-mongering for nothing
Steve.
>> Edited by Steve_T on Thursday 27th January 13:36
All this unfounded scare-mongering for nothing
Steve.
>> Edited by Steve_T on Thursday 27th January 13:36
Steve_T said:
Well said Snorky! I've been using Sainsbury's super unleaded recently, since it's only 2p dearer than regular unleaded (the one in Cobham just off the A3 for those in Surrey), not noticed any problemsor indeed any difference.
All this unfounded scare-mongering for nothing
Steve.
If you check out my earlier post then I think you'll find sainsbury's is supplied by BP
. Harry
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