Regular or super unleaded?
- Thread starter Sylvian
- Start date
I have a 987 and whilst I do try to always run it on the higher octane fuels, to be honest when I cant find it conveniently I hardly notice the difference when using ordinary unleaded. Some techies might know the answer for sure but I believe I read somewhere that the engine manageemnt system adjusts for the octane difference?
The engine management does allow for the reduced octane but it also means that the power is reduced in fact the majority of those I know say that for the cost difference V-Power is worth it on the economy alone. Given that it keeps the engine cleaner and gives smoother running with more power no point using anything else when it's available.
I've only ever used 95 octane when I couldn't get V-Power as happened a few weeks ago with the Tanker problem/panic!
I've only ever used 95 octane when I couldn't get V-Power as happened a few weeks ago with the Tanker problem/panic!
glewis
PCGB Member
I agree with Buddy. Before my current Cayman R, I had a Boxster S for 7 years. On the day I bought it, the Salesman at OPC Notts told me it would run on regular 95 unleaded but that they recommended 98.
Yes - it's more expensive, but not that much more, (depending on your mileage)- maybe £2 or or £3 on a tank full.
With the exception of £10 worth of regular 95 to keep me going in the "wilds" of the highlands of Scotland whilst trying to find a Shell forecourt, mine never ran on anytihng other than Shell V-Power or BP Ultimate and it always ran smoothly and performed well.
A Mercedes SLK230 I had before that definitley used to do more MPG if I filled it with V-Power, (or Optimax as it was back then).
If the additional cost of 98 octane is putting you off, check out your local Tesco. The one near me sells "Momentum 99" which is Tesco's 99 octane unleaded and it's about the same price as regular 95 unleaded at the nearby Texaco. I've tried a couple of tanks full in the Cayman now and seems to go well on it.
Yes - it's more expensive, but not that much more, (depending on your mileage)- maybe £2 or or £3 on a tank full.
With the exception of £10 worth of regular 95 to keep me going in the "wilds" of the highlands of Scotland whilst trying to find a Shell forecourt, mine never ran on anytihng other than Shell V-Power or BP Ultimate and it always ran smoothly and performed well.
A Mercedes SLK230 I had before that definitley used to do more MPG if I filled it with V-Power, (or Optimax as it was back then).
If the additional cost of 98 octane is putting you off, check out your local Tesco. The one near me sells "Momentum 99" which is Tesco's 99 octane unleaded and it's about the same price as regular 95 unleaded at the nearby Texaco. I've tried a couple of tanks full in the Cayman now and seems to go well on it.
Shell V Power every time if not available BP Ultimate
A month or so ago, due to a lack of availability of anything more exotic than 95 RON, I had to fill my 986 with that. Emptied that tank and filled with super unleaded and immediately my average fuel consumption improved by about 2 mpg. I use Shell VPower when I can get it, Tesco 99 and BP Ultimate rarely (Ultimate is only 97 RON so its not particularly "super"!).
Running V-power for instance allows for further ignition advance before detonation occurs. This not only effects full throttle activity inside the cylinder bore but effects partial throttle. Given the reasonably high compression from the Porsche engines, they are almost certainly detonation limited on full throttle and will definitely benefit from high octane fuel on partial throttle given the ability to read feedback through the knock sensor on the Porsche management is decent and adapts accordingly. More ignition = more power at partial throttle which means less throttle is required to obtain the same power output. Put simply, it's more efficient
Hi Guys,
Sorry and I know this subject keeps rearing its head but I think its important that we know the truth as to where the fuel comes from that we all put in our tanks.
Firstly, this is my chosen proefession, I am not "a mate in the trade" etc. Its what I do for a living. I run a fuel Terminal.
Supermarket fuel comes from the same tank as ALL of the other brands of 95RON fuel, if I was allowed I'd be able to post a pic of a BP truck queueing behind an ESSO, behind a Morissons, Tesco etc.
Its simply logistically impossible for trucks to load from their own depots so the big players all load from each others Terminals, the supermarkets just have contracts with each one as the market dictates.
The only fuel that is bespoke is from the Shell Refinery, "V Power" and that is refined and taken to the pumps UK wide.
Tesco 99 is mainly imported (at least in the North) and that is the only other fuel that is widely available that exceeds the 98RON that will be detected by our engines.
Additives are added by each Company but the doses are so small I am surprised they are allowed to advertise the supposed benefits on fuel economy and engine performance.
97RON or normal Super Unleaded (BP, ESSO, etc) is again all out of the same tank....
When Refineries have planned maintenance fuel is imported by ship but that still has to meet all of the quality standards.
The most common cause for poor quality fuel is a leak (water into) the petrol station tanks, or another similar problem, it is almost never the quality of the fuel that has been put into the petrol station tank.
Hopefully that helps people, I try and use V Power whenever possible, Tesco 99 when not, although I know the car will run well on any other fuel I use.
Cheers,
Matt
Sorry and I know this subject keeps rearing its head but I think its important that we know the truth as to where the fuel comes from that we all put in our tanks.
Firstly, this is my chosen proefession, I am not "a mate in the trade" etc. Its what I do for a living. I run a fuel Terminal.
Supermarket fuel comes from the same tank as ALL of the other brands of 95RON fuel, if I was allowed I'd be able to post a pic of a BP truck queueing behind an ESSO, behind a Morissons, Tesco etc.
Its simply logistically impossible for trucks to load from their own depots so the big players all load from each others Terminals, the supermarkets just have contracts with each one as the market dictates.
The only fuel that is bespoke is from the Shell Refinery, "V Power" and that is refined and taken to the pumps UK wide.
Tesco 99 is mainly imported (at least in the North) and that is the only other fuel that is widely available that exceeds the 98RON that will be detected by our engines.
Additives are added by each Company but the doses are so small I am surprised they are allowed to advertise the supposed benefits on fuel economy and engine performance.
97RON or normal Super Unleaded (BP, ESSO, etc) is again all out of the same tank....
When Refineries have planned maintenance fuel is imported by ship but that still has to meet all of the quality standards.
The most common cause for poor quality fuel is a leak (water into) the petrol station tanks, or another similar problem, it is almost never the quality of the fuel that has been put into the petrol station tank.
Hopefully that helps people, I try and use V Power whenever possible, Tesco 99 when not, although I know the car will run well on any other fuel I use.
Cheers,
Matt
Hi, yes I am sure all pump fuel will contain 5% (4.85) ethanol. It is added as it goes onto the truck and we have no option to load petrol without it. The neat petrol has a lower RON rating which is brought up to spec by the high octane bio-ethanol so the pump fuel would be off-spec if no bio-ethanol was added.
Like I mentioned earlier, V-Power is brought from the Shell Refinery so I do not know their process but the fuel does contain bio-ethanol, as does Tesco Momentum etc.
The bio-ethanol % will be raised in the near future too.
Diesel is similar, mixed with 7% bio.
Cheers, Matt
Like I mentioned earlier, V-Power is brought from the Shell Refinery so I do not know their process but the fuel does contain bio-ethanol, as does Tesco Momentum etc.
The bio-ethanol % will be raised in the near future too.
Diesel is similar, mixed with 7% bio.
Cheers, Matt
In view of what you have said above, I wonder if you would care to comment on this statement from BP then:-
From: careline@bp.com
Date: 05/06/2012 09:14:54
Thank you for your email concerning the fuel sold by BP.
In most regions of the UK our Ultimate Unleaded dos not contain any Ethanol at present (South West UK excluded). This may of course change in the future as the specification allows up to 5%.
Our Regular grade gasoline does contain up to 5% bio ethanol in compliance with EN228 gasoline specification allowance in most regions of the UK.
All BP fuels, regular and BP Ultimate, contain additives which have cleaning and protection properties for the engine. BP Ultimate has been rigorously tested on a wide range of vehicles, covering thousands of miles, in various conditions. Its advanced formula offers a wide range of benefits including better fuel efficiency, more power, better responsiveness, and lower exhaust emissions, all of which gives long term benefit and value to the consumer and their vehicle.
BP does not supply Bio Ethanol as a fuel.
Thank you for taking the time to bring the matter to our attention and for allowing us the opportunity to respond to your concerns at this time.
Kind regards,
Retail Customer Care Team
Regards,
Clive.
From: careline@bp.com
Date: 05/06/2012 09:14:54
Thank you for your email concerning the fuel sold by BP.
In most regions of the UK our Ultimate Unleaded dos not contain any Ethanol at present (South West UK excluded). This may of course change in the future as the specification allows up to 5%.
Our Regular grade gasoline does contain up to 5% bio ethanol in compliance with EN228 gasoline specification allowance in most regions of the UK.
All BP fuels, regular and BP Ultimate, contain additives which have cleaning and protection properties for the engine. BP Ultimate has been rigorously tested on a wide range of vehicles, covering thousands of miles, in various conditions. Its advanced formula offers a wide range of benefits including better fuel efficiency, more power, better responsiveness, and lower exhaust emissions, all of which gives long term benefit and value to the consumer and their vehicle.
BP does not supply Bio Ethanol as a fuel.
Thank you for taking the time to bring the matter to our attention and for allowing us the opportunity to respond to your concerns at this time.
Kind regards,
Retail Customer Care Team
Regards,
Clive.
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