Which Diesel

[phil1968]

Originally Posted by martin93

A petrol GTR will need V power fuel since it's a high performance engine with a high compression ratio, so therefore needs a higher octane fuel which burns slower. A lower grade fuel (less than 98 RON) will cause detonation or 'pinking', which causes a loss of performance.

However, I struggle to see what benefit V power diesel makes. I'm not knocking it (haha, 'knocking' it) because I haven't tried it. Diesel engines are a completely different ball game to a petrol GTR. They will always knock and detonate, because that's just how a compression ignition engine works. There's no such thing as an octane rating in diesel, because there isn't any octane. So I guess V power diesel just has more additives to make it burn cleaner? Whereas V power petrol has more octane to make the fuel burn slower and more controlled. A 'whoosh' more than a 'bang'.

Shell V-Power, along with all premium fuels has a higher cetane rating (which is the diesel equivilent to octane) than regular diesel fuel. I use a cetane booster added to the fuel in my D5 which works out cheaper than using premium fuel from the pump
https://www.youtube.com/watch?v=ezjknhwcQXU

[960kg]

Use Two Stroke oil as an additive as it ups the cetane rating a couple more points and also burns really clean so gives more power so therefore also runs quieter.

The 2T oil also lubricates the fuel pump as sulphur has been removed from the fuel which use to do the lubrication.




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[phil1968]

Originally Posted by 960kg

Use Two Stroke oil as an additive as it ups the cetane rating a couple more points and also burns really clean so gives more power so therefore also runs quieter.

The 2T oil also lubricates the fuel pump as sulphur has been removed from the fuel which use to do the lubrication.




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Do you have a link to verify that adding 2-stroke oil to the fuel ups the cetane rating? And what does it do to your DPF? I'm very dubious about this but am happy to be proved otherwise

[Tannaton]

Just on this subject I've seen a few threads recently with people questioning the quality of supermarket and budget brand fuels.

Bear this in mind...

There are only 6 oil refineries in the UK that produce fuel that is sold on forecourts for motor vehicles (excl. LPG).

https://notalotofpeopleknowthat.word...ning-industry/

Only two of those refineries is operated by a name you would recognise as a forecourt operator (Total, ExxonMobil), most petrol and diesel is refined by an entirely different company to a spec. Supermarkets and budget forecourt operators buy through contracts and on price - 9 times out of 10 its the same stuff that everyone else sells. Some companies do import also.

Most of the UK refineries are aged and operate at a loss but it is so expensive to close and de-commission the sites that it makes commercial sense to keep them running for now.

The extra chemicals added to the "go faster" fuels generally cost less that 1p per litre, the additional pump premium price is due to the dis-economy of the lower volume of sales but they do make more profit on it.

[skyship007]

Originally Posted by phil1968

Do you have a link to verify that adding 2-stroke oil to the fuel ups the cetane rating? And what does it do to your DPF? I'm very dubious about this but am happy to be proved otherwise

There have been several studies of diesel fuel additives that prove that the best additive to use if you are concerned about HP pump wear, is in fact Bio diesel. 2 stroke diesel made no significant difference. That study was used as the basis for changing the US fuel standards, as their fuel was causing some of the new Bosche pumps to fail.

Even supermarket diesel in the EU has more than enough Bio diesel added to avoid the new for adding any type of lubricant. What it can lack is additives designed to avoid long term gum deposits forming just inside the tips of the injectors. Tends to be more of an issue if you short trip a lot.

[Tannaton]

Originally Posted by skyship007

There have been several studies of diesel fuel additives that prove that the best additive to use if you are concerned about HP pump wear, is in fact Bio diesel. 2 stroke diesel made no significant difference. That study was used as the basis for changing the US fuel standards, as their fuel was causing some of the new Bosche pumps to fail.

I haven't been able to find it but I recently read a post on the LandyZone forums about this. There is a strong contingent of (older) Land Rover owners who insist on using 2 stroke mix oil in their diesel but a university did a study on it and found no discernible differences in emissions, wear or efficiency.

I will keep looking for it and post it if I find it.

[skyship007]

Originally Posted by Tannaton

I haven't been able to find it but I recently read a post on the LandyZone forums about this. There is a strong contingent of (older) Land Rover owners who insist on using 2 stroke mix oil in their diesel but a university did a study on it and found no discernible differences in emissions, wear or efficiency.

I will keep looking for it and post it if I find it.

Some of the Landy owners use veggie diesel and in some cases that fuel is real bad, so 2 stroke oil is probably better than nothing. Veggie fuel is bad news in both diesel bug (Nasty brown bacterial sludge) and injector fouling.

Using a good major brand fuel additive when using Bio or Veg fuel (Both are normally mixed with around 50% normal diesel) is a real good idea in winter in particular.

Oddly enough if you need to inhibit a diesel for a long storage period, it should be run on a 50/50 mix of engine oil and diesel fuel just before it is shutdown to protect the hp pump. Alas doing that does not protect the injector tips, so the injectors need to be removed and stored in engine oil when the cylinders are oiled or greased up.

[Waynedance]

I might just use shell regular diesel and buy a litre of Moly every quarter which would be approx every 3.5k for me and stick it in the tank.

[skyship007]

Originally Posted by Waynedance

I might just use shell regular diesel and buy a litre of Moly every quarter which would be approx every 3.5k for me and stick it in the tank.

Regular Shell diesel has all the additives needed (It might be worth using a can every 100K km) and even if you use supermaket fuel it's very unlikely that you would need to use a liter of LM Purge or other good fuel additive so often. Every 10K would be more than enough.

Most folks that use top of the range fuel are just wasting money, although it makes sense with a newish car to avoid supermarket or Indy fuel stations.

If you are really interested in protecting an engines from excessive wear, an occasional used oil analysis is worth it. Most of the main labs charge about 20 quid plus postage. I use Blackstone Lab in the USA, but there are others and even one in the UK.
A UOA report is the best way of figuring out if your injection system is OK, it's also a very good way of detecting HG leaks, bad air filtration and is by far the best way of figuring out when to change the oil.
I used to think that LM Synthoil was the dogs small round things, but when I compared results with Shell Helix, they were almost identical and far better than Castrol Edge, although the first 2 were A3/B4 and the last was the C3 version, so it might have been cos my engine likes Zinc based anti wear additives.

[Mtews]

I found my connect van tdci engine was smoother and better to drive with v power but mpg was the same so i stopped using it.