What petrol do we use

[geoff1]

When I bought my twenty year old 1600 vx from Paul Matty two years ago it had a handwritten note in the docs which said 'Please only put Shell V Power in this car'.

So being an obedient chap that's what I do.

Ian Payne of PT Sports said they had done some tests on Premium Petrol and V Power was the only one that made a difference. The theory is that it is the only 99 octane that has gone though an extra refining process where as all the others use additives to get the extra octane rating

Do we think this is right?

Perhaps anything would  work, except perhaps Diesel. 

 

[Geoff Brown]

As an older Seven your engine is probably tuned to running on full fat fuel where as most Sevens today are automatically tuned to run on 95 octane.

 

[David_Long]

There's no doubt that V Power can help solve issues on problem cars. I put it down to quality control as much as anything else. Generic supermarket fuels can be just as good, but when you are individually mapping engines and working at the limits of ignition, they are less consistent, and sometimes clearly not rated as described.

[OldAndrewE]

Agreed, I saw some tests reported some years ago where Shell V power was the best. The others had the octane rating required but V power also had a better calorific value i.e. more power as well as more resistant to pinking.  I only use V power in my modified classic mini (95 bhp) and will use it in the Xflow when it is back on the road

[David aka Blue7]

My CSR detests anything other than high octane such as V Power

[revilla]

My VVC K is mapped to run on 95 so any old pump petrol is just fine. Useful in a road car that does a lot of touring as you can just take what you can find.

[tangomikeromeo]

Like Revilla mine's mapped to 95ron so that's what it gets but I do look for Shell over supermarket fuel in case the stories of additives are true. 

That and the Shells in these parts are well placed for testing of the fuel in the usual manner. 

[StevehS3]

I run my standard 1600K on 95 and can't notice any difference with any fuel I've used. However, I have wondered if it is worth paying for more expensive fuel because of the [supposedly] better detergents.

[7 wonders of the world]

I mapped my 272 BHP Duratec on 95RON fuel as blatting Wales as 98RON is a little scarce - red diesel however is available on every street corner - so at least Pat will be happy....  

[CHRIS TODD]

I have a 1600X flow, with an car/engine that is from 1982, so just a little older than Geoff,s!

I used to run on Shell V Power but when touring found some more isolated parts of UK and Europe it was not available nor was any othe premium fuel. 

So I now but the cheapest supermarket 95 octone and I have a bottle of Millers Petrol Power Eco Max that increase tje octoane by up to 3 numbers. 

A bottle costing around £15.00 makes 500 litres and its as simple as just adding at the petrol station. If I am leaving fuel in the tank to stop rust in the winter I just increase the measure. Next season it runs perfectly from the first start.

Oh and it costs a fraction of Shell V Power at around 3p a litre over standaard fuel price!

 

[SLR No.77]

If mapping a predominantly road car it makes sense to do it on 95 RON fuel, but something decent of course.

On the road you're unlikely to notice any gain of having it mapped on 97/98 RON but you'll certainly notice if it's been mapped on 97/98 and you fill up with some dodgy fuel because it's all you could get in rural Scotland/Wales/France/insert your preferred touring location here. Common sense really.

Stu.

[Roy Blyth]

Years ago I tried different fuels in my 1980 crossflow and found that it generally ran better with V Power, so that's what I've stuck to.  It's still a leaded head and the only mapping available is Ordnance Survey....  

[Geoff Brown]

Further to the subject of most Sevens running on 95 octane & showing little or no difference running on 99 the spanner in the works is Bio Ethanol content.

When touring in Europe I occasionally had to re fill with 95/E10. Tried to avoid it at all cost filling up with E5 where I could.

It became apparent that the R400D did not like running on 95/E10 when idling in slow or halted traffic. There was a tendency for a very lumpy low tick over & more often than not if I was not quick enough with a touch of throttle the flame went out! 

Restarting was problematical involving turning the engine over for a short interval to blow residue out then resorting to a fair amount of throttle input to get the engine to catch. A spirited drive cleared the problem till the next set of slow or stationary traffic.

Back in UK just half a tank of fresh fuel cleared the problem.

I understand that the introduction of 95/E10 to the UK is currently under review. So more fuel problems? 

The only way out is to have the ECU bespoke programmed.

  

[TomB]

I think the super fuels have less, or possible no bio-ethanol which is a good a reason as any to use it.    

[SLR No.77]

My understanding though is that the use of more bio-ethanol in the mix is becoming a legislative requirement so it's going to be hard to avoid. I also know running a classic Mini that there's a lot of discussion in Mini circles about the damage it's doing to rubber seals in the fuel system and engine, something to be aware of if you experience problems.

My car was set up on 95 RON but if better fuel is available I'll often choose to buy it, it improves the average in the tank and I'm not doing enough miles that the increase in cost is an issue.

Stu.

[OldAndrewE]

There are two different circumstances:

Firstly "modern" engines with management systems that can be suitably mapped to use whatever fuel it is intended to use.

Secondly older engines with carburetors and traditional distributors with a fixed advance curve.  With these the type of fuel that is suitable will depend on how the engine was built (compression ratio, advance curve, etc.).  I am guessing that most of this type of engine in Sevens will have been built with power in mind meaning that they will suffer on lower octane petrol.  As already noted V power will meet the octane requirement and possibly also give a small power boost.

[geoff1]

Thanks all - but also re diesel, I seem to remember reading that Suzuki were working on a three pot diesel compression petrol engine with a spark rather than glow plug start cycle to replace the now defunct three pot that ended up in the 160

It would yield about 100 MPG in a Caterham which would be an interesting way forward 

Loads of low end torque so lower friction losses

Light as well

But I guess it got canned with all this electric malarkey

Geoff

 

 

[Golf Juliet Tango]

I mapped my 272 BHP Duratec on 95RON fuel as blatting Wales as 98RON is a little scarce

An expedition to Wales this year made me aware of that.  My 21 is booked in to Northampton Motorsport in early April to be remapped appropriately.

[rgrigsby]

#17 Mazda have brought something along these lines to market with Skyactiv-X technology.

As an aside, my 2.3l 250bhp Duratec running on an Emerald has switchable maps, I have a 98 map for use on track and a 95 map with retarded ignition for when I can't get hold of 98RON fuel.

Thanks

Robert

[SM25T]

We recently bought a CX-30 with a 2 litre petrol Skyactiv-X compression-ignition engine .... it achieves the required compression by supercharging.

[7 wonders of the world]

#17

glow plugs don't start the cycle in Diesel units (they aid cold start) - they are compression ignition, the heat of the compressed air is sufficient to ingnite the high pressure atomised fuel when injected directed into the chamber.

[D Jones]

The UK fuel distribution network is worthy of a separate post, but it is very simple.

Taking Buncefield (yes the one that went bang) as an example, it is connected to a pipe approx 600 dia that flows from the refineries to Heathrow and other distribution points around the country.

Each distribution point is known as a tank farm as this is where fuel is stored and separated, petrol tankers arrive from Tesco, asda, esso, shell etc. and fill up, they add their special product at the time they fill the tanker (this includes the red dye that is added to agricultural diesel)

Fuel, be it diesel, aviation or petrol is pumped through the single pipe and stored in one of the big silver tanks you may have noticed, when the fuel becomes a mixture of petrol and diesel, the mixed fuel goes into a different tank and left to separate and the heavier fuel pumped to its respective tank, followed by the lighter fuel, ready for the next mixed fuel that comes down the pipe.

So they may pump aviation fuel down the line on Monday and Tuesday with the majority going to Heathrow then on Wednesday morning a mix of aviation and diesel fuel comes through the pipe but by lunchtime it's pure diesel, friday morning its diesel and petrol mixed then petrol in the afternoon.

Hope that helps to explain the process  (I worked at Buncefield before the explosion) and no, it wasn't my fault !

The company that owned the pipelines was called BPA British pipeline association and the routing is covered by the official secrets act for obvious reasons, though I believe it's route is not very secret.

[richardm57]

https://www.esso.co.uk/en-gb/fuels/petrol?utm_source=Media&utm_medium=PaidSocial&utm_campaign=Octane2020&utm_term=Octane&utm_content=OctaneSocia

Hope this link works.

What do you all think.

[7 wonders of the world]

Linky:

https://www.esso.co.uk/en-gb/fuels/petrol?utm_source=Media&utm_medium=PaidSocial&utm_campaign=Octane2020&utm_term=Octane&utm_content=OctaneSocia

[Sooty]

My crossflow was jetted and timed on 95 ron and runs happily. I tend to give it a treat with 98 one tank in 4 and whilst there is a marginal improvement in pick up I'm not sure it makes a real difference. 

The bigger issue for me is the proposed switch to E10 as this will certainly push up the price of residual E5 to accommodate classic cars. I can see a replacement of fuel pipes and seals coming on.