Help me learn more about petrol
Discussion
I've played around mixing Toluene (pure hydrocarbon C7H8) into super unleaded to raise the octane. Pump fuel already contains toluene, i'm just adding more.
My M6 is mapped to 725bhp (dyno figure), thus runs higher boost and is therefore more susceptible to detonation at higher rpm with the ecu knock sensors inevitably doing their job and reining things in at higher ignition advance / rpm, especially when its warm and it loses its edge up top.
Using a 10% toluene mix (5l + 45l of petrol) by calculation raises the octane from 99 to 101 and a bit. (Toluene has a RON of 121). Put a cap full of gearbox oil in for some lubricating qualities and away you go.
At 20% mix you have 104 RON. As toluene has a much higher flash point it can make starting harder above 30% mixes, so call 30% a limit for road use. Turbo F1 cars (the old ones!) ran on 84% toluene.
30% mix would be 106 RON.
Also Toluene is denser than petrol and contains more energy / unit volume so it releases more energy in the combustion phase and it transfers more kinetic energy to the turbine of the turbo charger at the same time.
It does give the motor extra legs at the top end to the red line (last 1000rpm or so) but it's not very practical faffing with 5l cans of it the forecourt and really only something I played around with. Interesting though and something I'll try on other engines in due course.
At £1.18 a litre (for 50l) it's no more than fuel anyway.
http://www.worldofchemicals.com/428/chemistry-arti...
My M6 is mapped to 725bhp (dyno figure), thus runs higher boost and is therefore more susceptible to detonation at higher rpm with the ecu knock sensors inevitably doing their job and reining things in at higher ignition advance / rpm, especially when its warm and it loses its edge up top.
Using a 10% toluene mix (5l + 45l of petrol) by calculation raises the octane from 99 to 101 and a bit. (Toluene has a RON of 121). Put a cap full of gearbox oil in for some lubricating qualities and away you go.
At 20% mix you have 104 RON. As toluene has a much higher flash point it can make starting harder above 30% mixes, so call 30% a limit for road use. Turbo F1 cars (the old ones!) ran on 84% toluene.
30% mix would be 106 RON.
Also Toluene is denser than petrol and contains more energy / unit volume so it releases more energy in the combustion phase and it transfers more kinetic energy to the turbine of the turbo charger at the same time.
It does give the motor extra legs at the top end to the red line (last 1000rpm or so) but it's not very practical faffing with 5l cans of it the forecourt and really only something I played around with. Interesting though and something I'll try on other engines in due course.
At £1.18 a litre (for 50l) it's no more than fuel anyway.
http://www.worldofchemicals.com/428/chemistry-arti...
Edited by mikeN54 on Thursday 7th July 11:51
Only what i'd read online regarding adding lubricants to fuel additives. I use a full synthetic fuchs gear oil, not mineral. (had it in the garage already)
Gear oil has much higher shear strength and works under much higher pressures (i.e. DI 200bar fuel pumps and solenoid injectors) something 2 stroke was never meant for maybe?
Never considered 2 stroke, but a cap full in 50l of fuel probably wont make much odds anyway. I've got plenty of 2 stroke oil at home, even some Castrol A747 that smells like the old R. An M6 smelling like an old GP bike - interesting!
Gear oil has much higher shear strength and works under much higher pressures (i.e. DI 200bar fuel pumps and solenoid injectors) something 2 stroke was never meant for maybe?
Never considered 2 stroke, but a cap full in 50l of fuel probably wont make much odds anyway. I've got plenty of 2 stroke oil at home, even some Castrol A747 that smells like the old R. An M6 smelling like an old GP bike - interesting!
Edited by mikeN54 on Thursday 7th July 11:58
Trabi601 said:
loudlashadjuster said:
Trabi601 said:
Careful with those claims.
VPower comes from a single source, regardless of where it's being retailed.
Nothing I said contradicts that.VPower comes from a single source, regardless of where it's being retailed.
Also, while it is also my understanding is that Stanlow produces all V-Power, this obviously only applies to the UK.
There's some good stuff coming out in this thread, I'm enjoying the read. Patch5674 I've emailed you, thanks!
I haven't read through the whole thread so I might not be the first to say this but someone mentioned Alkenes and aromatics reducing knock propensity but didn't know why.
You were halfway there, you mentioned that the stronger bonds yield more energy when they're broken, giving more power/better fuel economy. Those stronger bonds cause a higher activation energy requirement for the reaction, hence needing a higher pressure/temperature to auto-ignite. This means you can have a higher compression ratio before then onset of knock the more of these constituents are present in the fuel.
Another vote for great thread OP, nice to see a change from bickering, nice to be reminded that PH is full of genuine experts as well as 'experts' who will give their time for free and have their contribution valued in return. Too often the true experts are shouted down by people who, frankly, don't know what they're talking about
You were halfway there, you mentioned that the stronger bonds yield more energy when they're broken, giving more power/better fuel economy. Those stronger bonds cause a higher activation energy requirement for the reaction, hence needing a higher pressure/temperature to auto-ignite. This means you can have a higher compression ratio before then onset of knock the more of these constituents are present in the fuel.
Another vote for great thread OP, nice to see a change from bickering, nice to be reminded that PH is full of genuine experts as well as 'experts' who will give their time for free and have their contribution valued in return. Too often the true experts are shouted down by people who, frankly, don't know what they're talking about
Great thread, OP! Sorry for being late to the discussions. I'm a fuels technologist with a chemistry and engineering background so am more than happy to answer any and all your questions!
I'd say these are the key things to know about petrol in the UK (many of which have already been stated):
- All petrol in the UK meets BS EN 228 (and diesel BS EN 590). These specifications guarantee a minimum QUALITY level, but have no PERFORMANCE requirements. It is important to understand this distinction. The right quality fuel can still result in engine deposits as this is not a mandated requirement.
- As said by others, all petrol comes from a system that meets the above spec but can still have variations in fuel composition (olefins, aromatics, etc.)
- To answer one of the OPs original questions: increased density does not necessarily result in increased calorific value - it depends on the composition.
- Octane grade stated at the pump is RON and specifies a minimum. Increased octane can be of benefit if your vehicle is calibrated to respond to >95 RON (like my GT86 is!)
- Fuel additives can result in benefits (such as cleaning injectors and intake valves) but it's not the case that having "some" additive in there is the answer. Fuels formulation is a balancing act so check which tests were run by a given supplier/brand to prove they work.
Please ask if you want to know more!
I'd say these are the key things to know about petrol in the UK (many of which have already been stated):
- All petrol in the UK meets BS EN 228 (and diesel BS EN 590). These specifications guarantee a minimum QUALITY level, but have no PERFORMANCE requirements. It is important to understand this distinction. The right quality fuel can still result in engine deposits as this is not a mandated requirement.
- As said by others, all petrol comes from a system that meets the above spec but can still have variations in fuel composition (olefins, aromatics, etc.)
- To answer one of the OPs original questions: increased density does not necessarily result in increased calorific value - it depends on the composition.
- Octane grade stated at the pump is RON and specifies a minimum. Increased octane can be of benefit if your vehicle is calibrated to respond to >95 RON (like my GT86 is!)
- Fuel additives can result in benefits (such as cleaning injectors and intake valves) but it's not the case that having "some" additive in there is the answer. Fuels formulation is a balancing act so check which tests were run by a given supplier/brand to prove they work.
Please ask if you want to know more!
luckystrike said:
battered said:
Aromatic hydrocarbons (with rings, eg benzene) are very energy dense, less volatile than linear HCs of the same C-chain length, and reduce knocking (not entirely sure why, prob less volatility).
As knocking is the product of detonation (rather than ignition) the reduced volatility would presumably be crucial to aromatic hydrocarbons reducing knocking. I'd hazard that the ring structure would provide a more stable molecular bond compared to an equivalent linear chain, thus making it less susceptible to breaking under increased temperatures driven by compression.Volatility is usually affected by the inter-molecular bonds - how strongly the molecules hols onto each other. Something very polar (positive at one end, negative at the other) like water has a very low voltility, octane with it's non-polar structure is much more volatile.
The energy available from a compound when it is oxidised (burnt) is directly related to the number of bonds between the different atoms. It takes energy to break these apart, this energy is then released when the individual atoms recombine in different combinations which have a lower 'resting state' eg CH4 + 2xO2 gives CO2 + 2xH2O + energy. If things take more energy to break open than they release from the new compounds, they won't burn - chemical reactions always flow to the lowest possible resting state. To reverse this (eg making metal from the oxides, you have to input lkarge amounts of extra energy).
Aromatic rings are special in the world of intra-molecular bonds. In it's simplified form, most bonds are formed of two different atoms sharing electrons. Some hydrocarbon rings do not have an aromatic bond and as such will break down more easily. The aromatic ring occurs when the carbon backbone of the ring structure evenly shares all the electrons around. It takes proportionally a much larger amount of energy to break open this electron 'cloud' than for a non-aromatic ring, thus the substance will have a much higher resistance to auto-ignition.
KuroKeeper said:
Great thread, OP! Sorry for being late to the discussions. I'm a fuels technologist with a chemistry and engineering background so am more than happy to answer any and all your questions!
I'd say these are the key things to know about petrol in the UK (many of which have already been stated):
- All petrol in the UK meets BS EN 228 (and diesel BS EN 590). These specifications guarantee a minimum QUALITY level, but have no PERFORMANCE requirements. It is important to understand this distinction. The right quality fuel can still result in engine deposits as this is not a mandated requirement.
- As said by others, all petrol comes from a system that meets the above spec but can still have variations in fuel composition (olefins, aromatics, etc.)
- To answer one of the OPs original questions: increased density does not necessarily result in increased calorific value - it depends on the composition.
- Octane grade stated at the pump is RON and specifies a minimum. Increased octane can be of benefit if your vehicle is calibrated to respond to >95 RON (like my GT86 is!)
- Fuel additives can result in benefits (such as cleaning injectors and intake valves) but it's not the case that having "some" additive in there is the answer. Fuels formulation is a balancing act so check which tests were run by a given supplier/brand to prove they work.
Please ask if you want to know more!
I have a simple question, but given your background I'm hoping your answer will be informative.I'd say these are the key things to know about petrol in the UK (many of which have already been stated):
- All petrol in the UK meets BS EN 228 (and diesel BS EN 590). These specifications guarantee a minimum QUALITY level, but have no PERFORMANCE requirements. It is important to understand this distinction. The right quality fuel can still result in engine deposits as this is not a mandated requirement.
- As said by others, all petrol comes from a system that meets the above spec but can still have variations in fuel composition (olefins, aromatics, etc.)
- To answer one of the OPs original questions: increased density does not necessarily result in increased calorific value - it depends on the composition.
- Octane grade stated at the pump is RON and specifies a minimum. Increased octane can be of benefit if your vehicle is calibrated to respond to >95 RON (like my GT86 is!)
- Fuel additives can result in benefits (such as cleaning injectors and intake valves) but it's not the case that having "some" additive in there is the answer. Fuels formulation is a balancing act so check which tests were run by a given supplier/brand to prove they work.
Please ask if you want to know more!
What brand/type of petrol do you put into your car when it needs fuel?
KuroKeeper said:
Great thread, OP! Sorry for being late to the discussions. I'm a fuels technologist with a chemistry and engineering background so am more than happy to answer any and all your questions!
I'd say these are the key things to know about petrol in the UK (many of which have already been stated):
- All petrol in the UK meets BS EN 228 (and diesel BS EN 590). These specifications guarantee a minimum QUALITY level, but have no PERFORMANCE requirements. It is important to understand this distinction. The right quality fuel can still result in engine deposits as this is not a mandated requirement.
- As said by others, all petrol comes from a system that meets the above spec but can still have variations in fuel composition (olefins, aromatics, etc.)
- To answer one of the OPs original questions: increased density does not necessarily result in increased calorific value - it depends on the composition.
- Octane grade stated at the pump is RON and specifies a minimum. Increased octane can be of benefit if your vehicle is calibrated to respond to >95 RON (like my GT86 is!)
- Fuel additives can result in benefits (such as cleaning injectors and intake valves) but it's not the case that having "some" additive in there is the answer. Fuels formulation is a balancing act so check which tests were run by a given supplier/brand to prove they work.
Please ask if you want to know more!
Thanks! Sorry for the delay replying but my hands have been pretty full. You just might regret that haha. Fuels technologist sounds like something very interesting indeed; I imagine you develop fuels and/or additives for one of the majors. I'd be very happy to be able to download your knowledge into my brain but alas, since the opportunity has arisen I'll have to make do with asking a few questions. I hope I don't bore you! I'd say these are the key things to know about petrol in the UK (many of which have already been stated):
- All petrol in the UK meets BS EN 228 (and diesel BS EN 590). These specifications guarantee a minimum QUALITY level, but have no PERFORMANCE requirements. It is important to understand this distinction. The right quality fuel can still result in engine deposits as this is not a mandated requirement.
- As said by others, all petrol comes from a system that meets the above spec but can still have variations in fuel composition (olefins, aromatics, etc.)
- To answer one of the OPs original questions: increased density does not necessarily result in increased calorific value - it depends on the composition.
- Octane grade stated at the pump is RON and specifies a minimum. Increased octane can be of benefit if your vehicle is calibrated to respond to >95 RON (like my GT86 is!)
- Fuel additives can result in benefits (such as cleaning injectors and intake valves) but it's not the case that having "some" additive in there is the answer. Fuels formulation is a balancing act so check which tests were run by a given supplier/brand to prove they work.
Please ask if you want to know more!
- Despite internet urban legend, I'm fairly confident all fuel supplied in the UK meets at least a modicum of performance regarding additives. In my case it's not really a concern as I run a brand new (i.e. 'clean') car on 99 RON fuels - both of which state they have multitudes more additives than their own respective base 95 RON fuel. I do note, however, that you made reference to it being a case of finely balancing the 'ingredients' rather than just throwing in 'some additive'. Does this mean adding things like Miller's Petrol EcoMax (or RedEx, or whatever) is fairly frivolous and not worth bothering with? For example, Millers assured me in writing that their additive would 'definitely' increase any UK fuel by 2 RON, giving effectively 101 RON fuel added to either Shell or Greenergy/Tesco 99. It would also guarantee standardised lubricity and detergency, they add, and could therefore be a cost effective alternative to buying V-Power. If I opted instead for Costco 97 RON (which is 107.9ppl versus 117.9ppl in these parts) and added Petrol EcoMax, they assured me it'd bring it to 99 RON with a full detergent pack. I tried it for a tank and didn't find it very effective however, with a loss of low down torque and high end power compared to the genuine 'full fat' stuff. Hence the question sparked by your comment.
- Giving further consideration to the two fuels in my OP (Momentum 99 and V-Power), just because they're both 99 RON and meet the requirements of my car. I have no doubt that Royal Dutch Shell and Greenergy put in a great deal of effort to making their respective fuels as good as they can, whether to a price point or to an intended performance standard. Shell does publicise the ISO tests it subjects its fuels to in order to ensure they're good at combating 'gunk and corrosion' (as they term it). Greenergy - via Tesco - have assured me they carry out similar industry standard testing on their own fuels, but that they feel the majority of customers are more concerned with EMPEEGEES than performance, so that's where they focus their literature and claims. That aside, for a modern turbo engine (2.0 TSI 220ps in my case) would it be better in power and economy terms to run on the higher MON, higher oxygenates, lower olefin/alkene fuel (M99) or on the slightly lower MON, less dense, lower oxygenate but higher olefin/alkene fuel (VPower)? Or is it a case of rolling the dice as it's impossible to say? As per my earlier comments, I don't actually find much between them in the real world, and since M99 is a fiver a tank cheaper I tend to stick to that lately. However, I can't shake the thought that Shell have a hell of a lot more experience and quite possibly a higher quality, more consistent end product. Could you add any comments, information or ideas? I realise your professional (and/or academic) affiliations may tie your hands somewhat here.
At the end of the day the price of petrol is still fairly trivial, certainly for me with my mileage and attitude to driving. I'd rather spend an extra £10 or £20 a week on 'expensive' branded petrol for hooning in the car than going to the pub/football/smoking/drinking/whatever. As with most drivers, I just want what's best for my car and to buy the fuel that will give me the most consistent power, torque, cleanliness - and yes, even economy benefits. I also just happen to have an insane thirst for learning new stuff, so feel free to give me both barrels about fuels/additives/whatever if you're in the mood for typing. I'm not lazy and would be just as happy to buy some textbooks or read some websites if you have any pointers that would save you time.
Cheers!
OP -
Watch out for additive manufacturers octane "points". They usually mean 1 point is 0.1 of a RON. So 2 points means from 99 to 99.2 RON. Many say "increase RON by 6 to 8 points" but this means 0.6 to 0.8 RON.
It's pretty well impossible to increase the RON by 2 of say 60 litres of fuel by adding say 200ml of any product. Most "boosters" contain toluene as their high octane aromatic with just some kerosene (diesel) for cleaning and oil for lubrication and dye to make it look pretty.
I'm adding pure toluene (with a little oil for lube) to my fuel and that needs 5 LITRES in 45 LITRES of fuel (10%mix) to raise RON by just 2 from 99 to 101.
PS I'd love to try momentum, but we have no Tesco garages within 20 miles at least but have at least 3 shell stations nearby! And when I have seen a tesco garage there's fifty cars queuing to get near it and they dont sell the usual garage stuff (paper, snacks etc). And we don't shop in Tesco in any case.
Watch out for additive manufacturers octane "points". They usually mean 1 point is 0.1 of a RON. So 2 points means from 99 to 99.2 RON. Many say "increase RON by 6 to 8 points" but this means 0.6 to 0.8 RON.
It's pretty well impossible to increase the RON by 2 of say 60 litres of fuel by adding say 200ml of any product. Most "boosters" contain toluene as their high octane aromatic with just some kerosene (diesel) for cleaning and oil for lubrication and dye to make it look pretty.
I'm adding pure toluene (with a little oil for lube) to my fuel and that needs 5 LITRES in 45 LITRES of fuel (10%mix) to raise RON by just 2 from 99 to 101.
PS I'd love to try momentum, but we have no Tesco garages within 20 miles at least but have at least 3 shell stations nearby! And when I have seen a tesco garage there's fifty cars queuing to get near it and they dont sell the usual garage stuff (paper, snacks etc). And we don't shop in Tesco in any case.
Edited by mikeN54 on Friday 8th July 08:47
mikeN54 said:
Watch out for additive manufacturers octane "points". They usually mean 1 point is 0.1 of a RON. So 2 points means from 99 to 99.2 RON. Many say "increase RON by 6 to 8 points" but this means 0.6 to 0.8 RON.
Well, I'll be damned... I bet I'm not the only one who just learned that! Thank you!mikeN54 said:
I'm not saying they all do that, but many do and the claims are all a bit wishy washy.
I was aware of that, which is why I emailed them to ask in the first place. I asked if they meant 2 RON (i.e. 97 to 99) and they replied that it 'definitely increases fuel by 2 octane', but like you I really don't see how adding something 1:1000 would do so! On reflection I notice they specifically said '2 octane' and not '2 RON' or '2 points'. Weasel words, perhaps?The ones that contain lots of MMT (Methylcyclopentadienyl manganese tricarbonyl - say that after a couple) do seem to give results of circa 2 RON or more in some cases. MMT at lower concentrations is in US (and elsewhere) petrol to boost octane instead of lead, I don't know if it's in UK fuels.
But from what I gather too much MMT is not good for CATs or lambda sensors and leads to plug fouling, so that's probably one to avoid?
Another benefit of using the 10-20% toluene mix that I use it is reduces the Ethanol content further and is perfectly stable, good news for old cars and garden machinery (or anything with rubber parts or a carburettor).
I buy it from here: (all in multiples of 5l containers, perfect to put in a 5l fuel can and add to 45l fuel)
http://darrantchemicals.co.uk/toluene
But from what I gather too much MMT is not good for CATs or lambda sensors and leads to plug fouling, so that's probably one to avoid?
Another benefit of using the 10-20% toluene mix that I use it is reduces the Ethanol content further and is perfectly stable, good news for old cars and garden machinery (or anything with rubber parts or a carburettor).
I buy it from here: (all in multiples of 5l containers, perfect to put in a 5l fuel can and add to 45l fuel)
http://darrantchemicals.co.uk/toluene
xjay1337 said:
I noticed much more responsive driving experience and increased MPG even on my standard Mk5 GTI.
It also seems to help keep carbon build up at bay.
So what ratio did you use to mix in with the fuel?It also seems to help keep carbon build up at bay.
I started at 0.75ml per litre and worked up to 2.5ml per litre for petrol.
MikeN54 that is a useful source of toluene.
Some folks use paint thinners (also made up of large amounts of xylene) which also contain methanol......more corrosive than ethanol. In low conentrations of 5%, the actual end concentration of methanol is pretty low. Best to check out the MSDS (safety sheet) for the composition of the products before you put it in the car.
One other thing to beware of is that there is no fuel duty paid on toluene, and it has a pretty distinct smell. You could fall foul of HMRC if using it on the road and get caught (did that happen once on one of those traffic cop reality shows?). Using at a track day however is just fine.
Some folks use paint thinners (also made up of large amounts of xylene) which also contain methanol......more corrosive than ethanol. In low conentrations of 5%, the actual end concentration of methanol is pretty low. Best to check out the MSDS (safety sheet) for the composition of the products before you put it in the car.
One other thing to beware of is that there is no fuel duty paid on toluene, and it has a pretty distinct smell. You could fall foul of HMRC if using it on the road and get caught (did that happen once on one of those traffic cop reality shows?). Using at a track day however is just fine.
xjay1337 said:
Sorry, if I was not clear I was talking about using Shell 99 
No worries. FYI I use Shell V Power in my Mcycle. It does make a difference on smoothness and MPG.Same with the Focus. Much better MPG as it is fitted with a knock sensor so picks up the change in fuel.
Little diff in the old Rover.
The acetone is an experiment I've been doing for sometime.
probably for another thread another day.
Edited by Spannerski on Friday 8th July 12:28
rainmakerraw said:
I do note, however, that you made reference to it being a case of finely balancing the 'ingredients' rather than just throwing in 'some additive'. Does this mean adding things like Miller's Petrol EcoMax (or RedEx, or whatever) is fairly frivolous and not worth bothering with?
Yes both fuel and lubricant formulating is a balancing act where adding one additive for one performance benefit can, and often does, have a detrimental effect on something else. In terms of lubricant additives then you are adding additives in the 1% or 0.1% quantities but with fuels its more the ppm (parts per million) level!Where I work there are extremely clever people doing this daily and engines running 24/7 to test it!
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