Question for you BiTurbo owners.

It will be quite happy running on normal diesel JoJo. Mine gets some premium diesel when it visits a race track/ 1/4 mile etc. The rest of the time I usually run it on normal Shell. I do put some 2 stroke in mine but I wouldn't recommend that with a DPF on the car.
 
Yeah - just regular for me, I have treated it to some super once but no discernible difference in performance or economy..... But from memory it takes the car a bit of time to learn a new fuel (or did I dream this????!!!)
 
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Yeah, after 14 years of S3 8L, and having V-power or GTFO drummed into me over the years, I was wondering if it was the same for this highly strung engine? I'm getting 25mpg during the school run, so hardlay making use of the power in stop start traffic. On the motorway though, it's just amazing and effortless.
 
same here, going to the pub picking the lads up on the way on country lanes im getting mid 20`s when I have to go on a run shopping it goes up to 43 ish not done that many miles in her so tend to have a lead right foot when I get the chance lol
 
Ok, so I filled up for the 2nd time last night, and I was on autopilot, and V-power diesel it is, it costs approx £72 to fill up with the fuel light on, normal derv would have been around £66. I averaged just under 30mpg using brim to brim figures. Not bad considering I took friends and family members out for quite a few blasts in it, to show them how miserable their own car is! Lol
 
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desertstorm said:
It will be quite happy running on normal diesel JoJo. Mine gets some premium diesel when it visits a race track/ 1/4 mile etc. The rest of the time I usually run it on normal Shell. I do put some 2 stroke in mine but I wouldn't recommend that with a DPF on the car.
Click to expand...


I would of thought adding 2 Stroke to the diesel would of been beneficial to a DPF equipped vehicle because it makes the diesel burn with less ash , also well known to reduce smoke opacity so less soot also to clog a DPF .
 
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Effects of 2t oil added to diesel cars.

Due to the pollution control measures of the EC diesel-oil is nearly sulphur free and contains up to 5% of bio-diesel. Sulphur has the property to grease the high pressure injection pump and the injectors. Without sulphur, the reduced greasing property of the new diesel has already shown negative impacts on the long-term stability of the injectors and the high pressure pump. The pump manufacturers have tried to react by lining the moving parts of the pumps with Teflon or other suitable material. However, the long term stability is still not achieved as with the old (sulphur contained) diesel.
The engine-research centre of a well-known German car manufacturer has conducted some long term tests of diesel additives to find out whether any one of them will have an impact on the long term reliability of the diesel engine components. This introduction to explain were my information comes from.
The results of this research: any diesel additive of any manufacturer presently on the market is not worth the money!
BUT: 2-stroke oil, which we use in our motor saws, lawn mower or in 2-stroke motor engines has shown to have an extreme positive impact on diesel engines, if such 2-stroke oil is added to the diesel in a homeopathic doses of 1:200. In practical terms: 0,300 litre of 2-stroke oil into the 70l diesel tank. The 2-stroke oil will be absorbed by the diesel (emulsion) and grease every moving part of the high pressure pump and the injectors.
Besides this, the 2-stroke oil will keep the diesel engine clean, as it burns cleaner as the diesel itself.
In other words, the 2-stroke oil has a much lower ash-content as diesel, when burned. This proven fact delays the DPF (diesel particulate (soot) filter) to clog, and the "burn free" process of the DPF will be much less.
More information: in Germany we have to present our cars every 2 years to the TUV -Technical Supervision Organisation - who will check, amongst others, the pollution of petrol and diesel engines.
The measured cloud-factor of a diesel engine without use of 2-stroke oil has been 0,95.
The same factor with the use of 2-stroke oil has been 0,47 - reduction of nearly half of the soot particles.
Besides this, the use of 2-stroke oil in the diesel will increase the mileage by 3-5%.
 
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To the original poster - the difference in diesel - there is no performance difference. Unlike petrol, it is only focused on "detergents". Gazwould has touched upon the reason why above.

I also would like to hear more about 2 stroke oil - I know this was necessary on older scooters. Any more details?
 
woollyjoe said:
To the original poster - the difference in diesel - there is no performance difference. Unlike petrol, it is only focused on "detergents". Gazwould has touched upon the reason why above.
Click to expand...

Are you 100% sure there are no performance benefits? My previous Passat Tdi with 230k on the clock had 10% better fuel economy using V-power on long runs. It didn't particularly feel quicker, but it was definitely more economical. Around down though, there was little or no economy increase.
On the Revo website, their remap for this car quotes a power figure, but states it depends on fuel quality, which hints at using V-power or similar for the best results.

I'll stick with V-power for the time being, I'll try the normal stuff at a later date, once I'm use to the poweeeeer! :D
 
100% sure yes. There are zero performance benefits. Economy is performance - they are the same thing expressed differently. I'm also 100% sure you believe there was a performance benefit but it wasn't the diesel.

I will also highlight the Petroleum companies do not claim any performance benefits with diesel but they do with Petrol - there is a simple reason, it doesn't help performance.

It only has added "detergents" designed to help keep the engine clean on the inside as direct injection is not ideal for this.

I'm not judging BTW about using premium diesel, it's your car and if it makes you feel better, why not.
 
Not sure where you are getting your information from about performance diesel but it definitely does make a difference. Fuels such as Shell V power and BP Ultimate are made differently compared to normal supermarket diesel.
Shell V power contains a good proportion of GTL (Gas To Liquid) diesel which is made as the name says from gas. It has a higher Cetane rating which is the equivalent of petrols higher Octane rating.Thats why it smells differently to normal Tesco diesel.

https://en.wikipedia.org/wiki/Shell_V-Power
There are many tests that have been done where Performance diesels have resulted in improvements. I have also noticed improvements in fuel economy when doing normal running using V-Power.

http://www.hertsad.co.uk/cmlink/har...performance_diesel_fuels_to_the_test_1_444715
 
Really????

Complete rubbish. From shell themselves: "Actual potential benefits relate to a detergency element which is designed to help clean-up existing deposits in your engine."

What they are saying is that the diesel doesn't improve performance, but assumes your car is underperforming. That video is a joke and not scientific at all. Run a car on the dyno and it will produce different BHP at the wheels every time.

Again - it only has "detergents" designed to compensate for problems created by the direct injection and the diesel changes over time.

"made differently" - eh no mate - you need to know how they are made and distributed before you start offering so called facts. SO you know - they come from the same place where some have "additives" added at the distribution points.

If you feel it makes a difference, help yourself, but these are not facts you are presenting.
 
My facts are from the manufacturers websites, the refineries and distribution points, as well as knowing a few people who work all the way upstream. That and a basic understanding of the diesel engine and chemistry.

I'm more than happy to accept petrol advantages as it is scientific in theory and practice to such a degree it can be consistently replicated in the real world, but with diesel, there is a lot of conjecture and marketing. Fifth Gear is a classic example. It's not even real journalism - just like using wikipedia.
 
So I've just found this info about BP Ultimate diesel.

With a guaranteed cetane rating of 55 compared to 51 for normal diesels, the performance advantage was only to be expected.
Click to expand...

I presume She'll V-power would be of similar/higher cetane over the standard stuff. So there has to be a performance gain, especially for tuned cars! Right?
 
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Just found this too.

Guaranteed minimum figures:-

Standard BS EN590: 51
Shell Diesel Extra: 53
Total Excellium: 53
BP Ultimate Diesel: 55
Shell V-Power Diesel: 55
 
If you believe that v power petrol has performance benefits why does it not show those on the Shell website ? It talks about corrosion inhibitors and cleaners but only calls the fuel a performance fuel. It doesn't talk about the RON value or how much faster/ more power your car will make .
http://www.shell.co.uk/motorist/she...o-plus/shell-v-power-nitro-plus-unleaded.html
Shell V-power diesel is also called a performance fuel on the shell website with very similar claims about it's other advantages but nothing about the extra power that is generated by an engine. These days it seems advertising your fuel to say it makes your car faster isn't the thing to do.

http://www.shell.co.uk/motorist/she...tro-plus/shell-v-power-nitro-plus-diesel.html

The Top gear test is valid, the hub dyno used in that test has very repeatable results. Regardless of the actual number when trying to calculate bhp that dyno would give very consistent readings.
With your basic understanding of diesel engines and chemistry why is it not possible for V-power diesel to make more power ?

All I can say it that my car runs better with Shell V power. Every time I fill the car I record the fuel used and what the car has been used for over the last tank on an Excel spreadsheet. Over the last 9 years of driving diesels I have always found V-power to improve mpg on like for like running.
I know all about running diesels on dynos I have run my old 130 PD Passat many times over the years whilst I was tuning it and remapping it.
I know a few things about tuning diesels and making them go quick as well.
Here's the trophy I won for the fastest diesel car on the quarter mile at last years GTI International.



The trophy for fastest diesel at Santa Pod GTI Festival 2014



Karl.
 
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http://www.researchgate.net/publica...e_number_on_a_premixed_diesel_combustion_mode

There are many very scientific papers around and they all say the same thing , Increasing the Cetane value of diesel fuel gives an improvement in torque and hence power. In a petrol car the increase in RON value allows you to increase ignition advance because the fuel won't detonate as easily, this gives you more power.
Modern cars use sensors to detect knock and continuously advance and ****** the ignition point to find the optimum ignition timing. Thus when you run higher octane fuel you can run more advance and you generate more power.
With most diesels the injection timing is fixed and determined by maps that vary that point dependent upon various parameters such as RPM, engine temperature etc.
Having a higher Cetane value in the fuel means that when the fuel detonates it does it quicker and reduces more heat. The net result of this is higher cylinder pressures and more torque.
 
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I would love to see the scientific cetane research please - really mean this without sarcasm as I have explored this at great lengths looking for evidence.

Most modern diesels and petrol engines do not suffer from the things these fuels fix. It is a misunderstanding of RON and Cetene, although the detergents I'm more unsure about as it is hugely unknown with modern cars.

RON and Cetene is about controlled burning of the fuel. Stick Ron 98 in a car that is fine with RON95 like the RS7 and it makes no difference.

Stick RON 98 in an older car that suffers from uncontrolled burn (possibly made worse by tuning), then yes it makes a difference. This post is about the BiTDI so does not require the performance diesels.

The point is simple. The case for "performance" fuels is hugely miseld by marketeers. I know because I am one.

I and this thread won't end with an answer (they never do), if you feel the BiTDI will benefit from performance diesel, why not. If you want to believe you get extra horse power, sure.
 
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I would like to see the effects of that tuning box on engine performance as well. Most dyno sessions will do something like 3 runs, so 1 with no tuning box, one with tuning box in eco mode and 1 flat out.
I can recommend MRC in Banbury, not a million miles from you.
 
This paper seems to detail quite well the improvements in engine performance and emissions with diesel that has a higher CN number.
http://www.iasj.net/iasj?func=fulltext&aId=24812
Looking at the conclusions
Improved fuel economy with higher CN fuel.
"The bsfc reduced compared to the baseline diesel. The maximum reduction reached (at constant speed and variable engine loads) was for diesel fuel with CN=55. The reduction was 12.55% compared with baseline diesel fuel. While at constant load and variable engine speed the reduction reached was 5.5% for diesel fuel with CN=55. "

Increased power
" Brake power increased with increasing fuel cetane number. The maximum increment achieved was 5.6% for diesel fuel with CN=55 compared with baseline fuel."

A quieter engine
"Engine noise reduced remarkably with increasing CN."

Reduced emissions
" 6. NOx emissions decreased simultaneously when diesel engine fueled with higher CN diesel fuels. The maximum reduction attained was 6% for diesel fuel with CN=55 compared with baseline fuel.

7. CO emission decreased with the increase of CN rating. The maximum reduction attained was 30.7% for diesel fuel with CN=55 compared with baseline fuel.

8. HC emission reduced by increasing CN rating of the fuel. "

The test above is using a baseline 49CN fuel , it seems in this country normal diesel is 51CN and performance diesels are 55CN .
 
woollyjoe said:
RON and Cetene is about controlled burning of the fuel. Stick Ron 98 in a car that is fine with RON95 like the RS7 and it makes no difference.
Click to expand...
I can tell you that a high performance car such as the RS7 will make more power on RON 98 fuel than RON 95. This isn't for an RS7 it's for a BMW 335i but you can see the car makes a good deal more power on 98 RON
http://www.e90post.com/forums/showthread.php?t=348050

An RS7 will happily run on normal unleaded but it will run a lot better on 98 RON.

This is for an older ECU design, modern ones are much more complicated, but it explains the basics of ignition advance maps and how they are dynamically adjusted to optimise the engine. Because of the feedback from the knock sensor the ECU is able to make corrections to the ignition point many times every second.
http://www.stealth316.com/2-ignitionsystem.htm

A modern petrol engine will quite quickly advance the ignition timing when a higher RON fuel is used and the effect is usually more noticeable on a petrol engine. Changes in a diesel are more subtle but still there.
 
Al-Khwarizmi Engineering journal? Really. Do you not think it might be biased. Besides - it is engine dependant. Not the kind of reaearch i can trust and again, i'd love there to be proven benefit.

The RS7 i'm told performs no different with higher than ron95 by audi uk - happy to be educated though.
 
Fuel is a hydrocarbon and it is this that burns. It's energy potential is fixed. Scientific fact.

The additives to increase octane or cetene only help to burn at right time. No extra power. It is impossible. Energy is transferred not created.

However if the fuel contains more hydrocarbons (the stuff that burns and creates energy) then you have more power. This is nothing to do with RON or cetene- BUT fuel companies can make the fuel slightly denser to increase power.

This is the only way you get more power. I'm pretty sure the fuel companies started doing this recently to help market a more premium product. It is not the cetene rating though. I don't believe its enough to feel a difference but it makes "a" difference.

Denser fuel is a trick that can be used to genuinly increase power output (in the physics sense - not car). The combustion engine wastes most of the energy so 1% more HCs might equate to 0.3% improvement in HP at the crank before its reduced further to the wheels.

The big sell is based upon the Premise that assumes your car is under performing and it will fix it. But again, the car is already designed for standard diesel for maximum performance. Same for RS7 - it was designed for RON 95 for optimum performance. Filling it with RON 98 doesnt fix anything.

So if you have a BiTDI engine, you may get an improvement but only if the fuel is denser with Hydrocarbons, not the additives.
 
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woollyjoe said:
Al-Khwarizmi Engineering journal? Really. Do you not think it might be biased. Besides - it is engine dependant. Not the kind of reaearch i can trust and again, i'd love there to be proven benefit.

The RS7 i'm told performs no different with higher than ron95 by audi uk - happy to be educated though.
Click to expand...

Why is the research likely to be biased ??? . The basics of the diesel engine are no different in the BI-turbo, fuel is introduced into a cylinder gets compressed and it goes bang. With a modern diesel there are multiple injection events to improve NVH , emissions , economy and to deal with DPF regeneration etc but the same improvements in performance, economy and emissions are seen with diesel that has a higher CN number.

More so in an engine that runs to much higher RPM than a lot of diesels. As engine RPM increases the time available to inject fuel and get it to completely burn becomes very short. This is where fuels with a higher Cetane number really score.
Cetane is the key measure of diesel fuel combustion quality. It relates to ignition delay - the time between fuel injection and combustion. Good quality combustion occurs with rapid ignition, and then smooth, complete fuel burn.
With a higher cetane number Diesel burns more smoothly and completely. So it releases energy more efficiently, which contributes to better engine performance.
It's not just the amount of energy that's present, it's how fast you can get it out.
 
This is where the internet is bad - lots of people reading wrong information and then assuming it's correct.
desertstorm said:
Why is the research likely to be biased ???
Click to expand...
The research is unscientific, is not published in a reputable journal. Its also likely to be biased and whilst my opinion is guesswork - its not rocket science when you consider where its from if you have basic understand of the oil industry. Either way - it is poor science.

desertstorm said:
The basics of the diesel engine are no different in the BI-turbo, fuel is introduced into a cylinder gets compressed and it goes bang.
Click to expand...
Misleading to say basics of diesel and the BiTDI are the same -we're not talking about basics. The cycle hasn't changed but the advancements are drastic. The overall technology has advanced to incredible levels I don't think should be taken for granted. You are misunderstanding where the differences are.

desertstorm said:
the same improvements in performance, economy and emissions are seen with diesel that has a higher CN number.
Click to expand...
Just not true - this is engine dependant but Govt has now set minimum limits on the cetene and RON. For the BiTDI, the level it requires is standard diesel which is actually very good.

desertstorm said:
More so in an engine that runs to much higher RPM than a lot of diesels. As engine RPM increases the time available to inject fuel and get it to completely burn becomes very short. This is where fuels with a higher Cetane number really score.
Click to expand...
Incorrect, RPM is not a factor certainly in the BiTDI and most modern engines are working as designed. The only fact is that time is shorter (which is obvious), but this is not where higher cetane helps - beyond what it needs.


desertstorm said:
Cetane is the key measure of diesel fuel combustion quality
Click to expand...
Complete made up nonsense. The hydrocarbon density is way more important. Cetene is much less relevant because the Govt now sets minimum standards for the pumps (for all suppliers). Improving cetene beyond what the car requires is pointless. Combustion quality?

desertstorm said:
With a higher cetane number Diesel burns more smoothly and completely. So it releases energy more efficiently, which contributes to better engine performance.
It's not just the amount of energy that's present, it's how fast you can get it out.
Click to expand...
The injectors dictate how much vapour mix is burned - not the cetane rating. The smaller the particles the better the burn. This is what factors to the energy released (in the physics definition of energy - not car Power). The "how fast you can get it out"?

This is all myth read from the internet, more fuel density is the only way to release more actual energy from fuel. If the mixture is not burning right then it is wasting some of the fuel by not burning because the fuel particles are not small enough or balanced with the right air mixture. I'm sure they may be finer details, as I'm more physics that mechanic.
 
desertstorm said:
Much like the RS7 being set to run and make power on 95 RON fuel the diesels will be set up for 51CN
If you want to make your own super diesel then get some 2-ehn and dose up normal 51cn pump diesel to 55cn. 500:1 would work.
http://www.oilem.com/tag/2ehn/

http://www.ebay.co.uk/itm/2-EHN-Hig...464625?hash=item2ed21ac231:g:lA4AAOxy3yNThHQP
Click to expand...
Stick that in your BiTDI and I'd happily bet cars your MPG drops. This stuff was designed back when we had leaded petrol.
 
my lawn mower likes v power petrol :)

my dad always blames rubbish diesel in france for doing in his throttle boddy on his old car (think thats what went lol )
 
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There used to be a situation where petrol / diesel quality differed hugely and this is where the supermarkets are seen as inferior quality - because they used to be inferior. Now the govt has set minimum standards and it's all the same. Pretty sure it was hugely variable over Europe too, but again there is EU regulations.... Standard of fuel today is very homogenised and good as standard.

For some, that image / memory never went away and I can understand the distrust.
 
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