What fuel

[KeatV70D5SE]

Has anybody experienced any problems using supermarket fuel? I have a D5 V70 and usually use "Jet" fuel. Is it worth paying the extra for "brand name" fuel.

[ShadeTek]

Well, you have to ask the qustion why is supermarket fuel cheaper? Has it less lubricants etc in it? I heard a machanic saying that supermarket fuel is not as good as normal fuels for this very reason. True/False?...I dunno.

When I first got my T5, I asked the volvo specialists what fuel to use in it (having read the arguments on here about Optimax, Ultimate etc.). Their reply was....petrol! I asked Sainsbury's who supplies their fuel, including their super unleaded. Their answer was BP, so I reckon their superunleaded could well be Ultimate. Fuel has a BS standard for it and a RON rating. If it was no good, they would not be allowed to sell it.

On the question of price....how do supermarkets sell 500ml bottles of coke cheaper than petrol stations? Because they have huge purchasing power, and survive on perhaps smaller profit per sale, but with millions of sales. You only have to go to a cash and carry to see how cheap you can buy coke, and then compare that price to the rip off they charge in petrol stations.

I am currently putting in whatever is convenient and cheap. I did feel a little smug using Optimax, but seeing as my T5 is a 95 and doesn't have variable valve timing, I can't make the most of the increased octane content in the fuel anyway.

I don't know.....sometimes I think it is psychosomatic...but I am almost over the "pay £3.00 more per tankful" phase of my T5 ownership. If I notice anything really detrimental I will go back and experiment with the more expensive fuels.

BTW...Sainsbury Super U/L 79p per litre, Ultimate 87!!!!!p per litre, Optimax 86 p per litre (in Bracknell).

Richard Whennell
855 T5 1995
VOC member

[sarge]

I used to use supermarket fuel until Ultimate arrived in town (never had Optimax here). The supermarket stuff never gave any real problems but on BP Ultimate the car is more responsive, doesn't produce sooty deposits on the bottom edge of my exhaust pipes, and the improved mpg actually compensates for the extra cost of the fuel. The supermarket fuel may not be bad, but in my mind the pricier stuff is better.

Sarge
'99 V70 AWD

[sholtby]

Sainsbury Super unleaded at 79 ppl would be my choice. Do many supermarkets sell super unleaded?

Simon

As mentioned above. All fuel offered for sale in this country has to meet BSI standards. If the fuel dosn't meet these standards then it has to be withdrawn from sale.

As for Optimax and Ultimate, to be honest unless your car has been highly tuned then you wont really notice any difference when it comes to performance. I didn't but some other people will swear by optimax.

I shop in Sainsbury's and at the bottom of the recipt is a money off petrol voucher. So I get my petrol at Sainsbury's petrol station. At the moment 95 RON normal Unleaded is 79.9ppl. With the money off voucher I get 4ppl deducted. So petrol is costing me 75.9ppl and this adds up in the long run.

When I took my V70 for its MOT, the emmisions test showed that the fumes coming out the back were better than its first ever MOT.

[liuleichan]

>I am currently putting in whatever is convenient and cheap. I
>did feel a little smug using Optimax, but seeing as my T5 is a
>95 and doesn't have variable valve timing, I can't make the
>most of the increased octane content in the fuel anyway.

I'm largely with you on the supermarket / vs forecourt petrol thing - they are all businesses, and will all try and source their fuel at the cheapest price.

However, your comments about variable valve timing don't make the greatest of sense. VVT isn't about coping with differences in fuel, per se, they are more about getting more flexibility from an engine.

The knock sensor and other electronic gadgetry tends to control the spark timing.

VVT is more about being able to provide torque at low engine speeds, whilst being able to leverage better breathing from mulitple valve engines at high engine speeds.

Basically, it's to counter the effect or characteristics that made multi-valve engines great at high revs, but gutless when below their power band.

Some implementations also use it to help with fuel economy.

Different engine manufacturers implement in in different ways, with some, it's merely cam timing influenced by electro-hydraulic interference at certain rev points. Some implementations it's more gradual. Some implementations only affect some of the valves. Some implementations do more than just alter the timing of the valves - with some it affects how much the valves open, as well as how long and at what points.

But the timing WRT octane rating is slightly separate and usually done through knock sensors (basically "special" microphones) and the ECU software advancing, or retarding the spark timing.

I don't think Tesco offer superunleaded. Sainsbury definitely does (97 not 98 RON). Esso also does super unleaded which is generally cheaper than Optimax or Ultimate. Sainsbury super unleaded is usually only a couple of pence more than 95 RON, as opposed to the 6 or 7 pence difference that Shell or BP extort for the same privilege.

Thanks, Liu, for explaining the VVT thing. Knowledge is power!

Richard Whennell
855 T5 1995
VOC member

Another interesting thing is what octane means. I thought it meant power as in HIGH OCTANE FUN... but it is the name of the actual petrol...like methane, propane, hexane...etc. The number 8 is involved...something to do with the number of hydrocarbons joined together to make the fuel. The higher the octane rating (or content?) the quicker the fuel will ignite. I am sure if someone has the energy they can correctly explain the facts that I have just mixed up!

There is an amazing website called howitworks.com with a whole bunch of really cool information. I had a read about auto gearboxes and now have a small idea of just how complicated they actually are.

Richard Whennell
855 T5 1995
VOC member

[JXBURNS]

Having worked for an oil company for last 20+ years (on sea-going tankers), we used to load unleaded fuel and physically add the lead additives when we were at sea in hope it would mix by the time we reached the discharge port. A bit of a hit & miss affair so nowadays it is done at the refinery.

I digress.. In the UK there are few refineries that produce petrol in any large quantities but most are connected by fuel pipelines across the country to local distribution terminals. The resulting product must meet the same international standard so does not matter where you buy it from unless it has gone "off spec" (e.g. due tank or water contamination) and has to be downgraded.

Supermarkets do not have any legal requirement to stockpile fuel - in UK I believe oil companies still need to hold at least 3 months worth of strategic reserves. This I guess will bump up the fuel price by a small percentage. But just sit outside BP Coryton (Essex) and watch the Sainsbury & Tesco lorries coming out every morning - that will tell you where the fuel comes from...

John