Petrol

[ekay1]

Would you guys recommend BP ultimate for best burning too? Ive switched to BP recently, and it seems to be giving me better efficiency. If it burns better, wouldnt it eat up more fuel?

[jyh888]

Agreed, BP ultimate tried and tested for best mileage

[curtis265]

BP won't be around for much longer though.

[Nairda]

i havent got an FD yet but id probably stick with V-Power or RON95....standard unleaded should give you -1L/100km over cheapy fuels and E10, premium should give you another -1L/100km.

I worked it out and its more economical to buy normal RON95

At the moment in my ED3: E10 + caltex(safeway) petrol = 9-10L/100km, shell unleaded 95 = 8-8.5L/100km, V-Power 7-8L/100km? (not sure havent tried it but that would be my estimate)

[FDBenni]

i doubt it will make that big of a difference in a FD, the difference between standard and premium would probably be 0.5l if that. I still use the premium though since it feels slightly more responsive(could be placebo effect) and helps with the pinging.

[Nairda]

Would you guys recommend BP ultimate for best burning too? Ive switched to BP recently, and it seems to be giving me better efficiency. If it burns better, wouldnt it eat up more fuel?

Not necessarily...quality of the fuel depends on the content of hydrocarbons inside the solution and impurities...

Let me educate you a little since im studying organic chemistry =P

Octane content is important because it gives off a good amount of energy when you burn it and it forms CO2 and H2O being more stable than a long hydrocarbon chain. According to wikipedia it gives off standard enthalpy of −5430 kJ/mol in combustion. (Enthalpy = the change in energy when a reaction occurs. "-" means exothermic reaction and energy is given off, positive integers means endothermic and energy is absorbed)

Fuels that dont have as much of these nice long chains (Octane +) and have more Ethanol (E10) and thus do not give as high energy when burnt. Wikipedia suggests that Ethanol's standard enthalpy for combustion –1370.7 kJ/mol.

So from these figures you can see that 1 mol of octane gives off more energy when combusted (which is expected because octane has more carbons and more hydrogens, as well as one mol of octane is heavier than ethanol). However as it turns out i just worked out the Molar Mass of ethanol which is 46 and octane is 114.. so actually in octane you are getting 2x the amount of energy per mol combusted even when you get near equal mass amounts

Also quality of fuel takes into account less impurities such as sulfates that are usually found inside crude oil so when you talk about "Good quality fuel" such as VPower and Ultimate, they have less impurities because they have been processed that much more (more filtration, purer fractional distillation)

Therefore the "purer" the fuel, the more energy you actually obtain from the combustion because theres more hydrocarbons per drop....less impurities such as sulfates that dont give off a lot of energy when combusted. Pure ethanol also vaporises quite quickly so you may actually "lose" a little in the combustion process. (which is the fuel smell when you open your filler cap...some fuel has vaporised)

Thus in comparison your engine works like this:
I need X amount of energy to accelerate from 0 - 80km/h and with fuel with no ethanol it takes "O" amount
the same X energy for acceleration from 0 - 80km/h requires "E" amount from E10 which is a x% more than the amount "O"

So every time your car needs to get up the same hill, will need to use that much x% more E10 than O

I hope this deserves a PQ point =)

[Nairda]

i doubt it will make that big of a difference in a FD, the difference between standard and premium would probably be 0.5l if that. I still use the premium though since it feels slightly more responsive(could be placebo effect) and helps with the pinging.

i ran with United E10 for a month and then compared it to running Caltex Safeway and then Shell Unleaded using iphone road trip program...so it wasnt a psychological conclusion =P...based on organic chemistry it would have an affect depending on the quality and purity of fuel you get

[FDBenni]

Might be true for your car but not the FD. I was able to achieve 7l/100km on standard unleaded, but there's no way I can get 5-6l/100km using premium unleaded if driving style was unchanged. It's hard to really test the differences unless you have IDENTICAL trips, there probably are differences but not as big as you claim.

[Nairda]

of course its not a linear relationship...im pretty sure you cant go as low as 5 or 6 because honda must have tested their initial reading with the best fuel they were capable (probably in japan with their RON100) so whatever they state on their website is like the very best you can get...none of us will get 6.9 on the stuff australia gets...you will get 6.9 if you do highway driving and use V-Power Ultimate of that im pretty sure.

As i said before the differences were going from cheapy United E10/Caltex Safeway Unleaded and Shell Unleaded....i havent tried (and probably wont anymore on my bomb) using V-Power. But its incredibly likely that if you want to get the minimum fuel consumption, your best bet fuel to use would be the premium types

[ekay1]

i doubt it will make that big of a difference in a FD, the difference between standard and premium would probably be 0.5l if that. I still use the premium though since it feels slightly more responsive(could be placebo effect) and helps with the pinging.

AHaha, i think i fell forn the placebo effect when i used BP ultimate xD
And guys, how much does everyone run on a full tank? and how much fuel is left whne the light turns on. Cause today, the light turned on when it had 2 bars left, and i got worried so i refuelled. Plus, last time, when i went to refuel, and the gauge JUST dropped to every bar gone, i filled up 40L to full. However, in the manual, it reads that the has 7.5L left once the light turns on. Whats going on T_T
and on average, ive been getting bit under 400k's on a fuel tank on a new FD1 auto.

[FDBenni]

too scared to test the limits but its about 10 litres or so, so maybe you can drive a further 100km with the light on. Either way I think you'd want to start looking for a petrol station at 1-2 bar, haha.

[curtis265]

when the light comes on i fill and get 42L. ( and no bars)