Is Super Unleaded Needed In my Boxster?
Discussion
muff666 said:
Hi
i was wondering if anyone out there has tried to use normal unleaded in there porsche boxster? i have a 1998 Boxster 2.5 and was wondering if i could use normal unleaded??
Many thanks
Muff666
More than likely - the engine ECU will just adjust the timing to cope and give you slightly less power. It should say in the handbook.i was wondering if anyone out there has tried to use normal unleaded in there porsche boxster? i have a 1998 Boxster 2.5 and was wondering if i could use normal unleaded??
Many thanks
Muff666
I think not ..............
Super Fuels
Many of the large petrol companies have launched 'super fuels' - petrols and diesels that have a higher research octane level. These fuels are said to increase power in many vehicles, deliver less pollution than regular fuels and help to maintain a cleaner engine. Amongst these 'super fuels' are Tesco's Super Unleaded 99 Octane petrol, supplied by Greenergy, now sold at many stations across the UK and also BP's Ultimate 102 Unleaded which is currently the most advanced, high-performance petrol you can buy on UK forecourts.
Using Super Fuels
One of our users commented that using higher octane fuel than your engine requires actually gives no benefit and may be a waste of money. This is because virtually NO engines require 98 RON over 95, and the market for 'super' fuels seems to be based on people's misunderstanding of octane ratings and the placebo effect of filling up with 'more powerful' fuel - making motorists think their engine is running better in some way.
What do the fuel companies say then, to justify the "increased power" claims for the super grade fuels? Some companies say that while all fuels contain cleaning additives, 'super' fuels contain more or better detergents to keep the injectors cleaner than standard fuel. Others say the fuel is a few percent denser which gives slightly more power per litre. These benefits may be marginal though in comparison to the extra cost involved so it is worth ensuring that your engine will actually benefit before filling up.
Some engines actually do need higher octane fuel, such as race engines with very high compression and some turbocharged engines, such as the import version of the Nissan Skyline. Also, a few vehicles, such as the new BMW K1200R motorbike, can sense knock and adjust their engine tuning to take advantage of higher grade fuels. Another user commented that the 2004 BMW 330 also does this, according to the driver's handbook it makes 231 BHP on 98 octane and 221 BHP on 95. This ability is apparently widespread amongst German performance cars using Bosch / Siemens electronic engine controls.
For further information on the major fuel companies fuel options see their individual information pages:
Super Fuels
Many of the large petrol companies have launched 'super fuels' - petrols and diesels that have a higher research octane level. These fuels are said to increase power in many vehicles, deliver less pollution than regular fuels and help to maintain a cleaner engine. Amongst these 'super fuels' are Tesco's Super Unleaded 99 Octane petrol, supplied by Greenergy, now sold at many stations across the UK and also BP's Ultimate 102 Unleaded which is currently the most advanced, high-performance petrol you can buy on UK forecourts.
Using Super Fuels
One of our users commented that using higher octane fuel than your engine requires actually gives no benefit and may be a waste of money. This is because virtually NO engines require 98 RON over 95, and the market for 'super' fuels seems to be based on people's misunderstanding of octane ratings and the placebo effect of filling up with 'more powerful' fuel - making motorists think their engine is running better in some way.
What do the fuel companies say then, to justify the "increased power" claims for the super grade fuels? Some companies say that while all fuels contain cleaning additives, 'super' fuels contain more or better detergents to keep the injectors cleaner than standard fuel. Others say the fuel is a few percent denser which gives slightly more power per litre. These benefits may be marginal though in comparison to the extra cost involved so it is worth ensuring that your engine will actually benefit before filling up.
Some engines actually do need higher octane fuel, such as race engines with very high compression and some turbocharged engines, such as the import version of the Nissan Skyline. Also, a few vehicles, such as the new BMW K1200R motorbike, can sense knock and adjust their engine tuning to take advantage of higher grade fuels. Another user commented that the 2004 BMW 330 also does this, according to the driver's handbook it makes 231 BHP on 98 octane and 221 BHP on 95. This ability is apparently widespread amongst German performance cars using Bosch / Siemens electronic engine controls.
For further information on the major fuel companies fuel options see their individual information pages:
It will wind back the ignition if you use 95 Octane, which will reduce power and efficiency slightly, but bear in mind that the method for detecting 95 Octane is to detect the pre-ignition (i.e. pinking/knock), caused by the lower quality fuel.
So basically, the engine will have to preignite before it winds back the ignition. Some strategies are better than others, and it's far more critical in turbo-charged cars than it is in normally aspirated ones, but really you should just consult your car's manual. If it says only use 95 in an emergency then do so, but if it says something like '95 minimum Octane but your car will run better on 98', then you can switch between the two.
Personally on a relatively high specific output car like a Boxster or 911, I'd stick to Super, specifically V-power, as it's got far better detergent and lubrication properties, which could prolong the life of things like injectors, and reduce carbon deposits.
Also, Octane it's nothing to do with the density of the fuel or any cobblers like that, if anything 95 has more energy content than Super, particularly Tesco 100 as it's got Alcohol in it to boost the Octane rating.
So basically, the engine will have to preignite before it winds back the ignition. Some strategies are better than others, and it's far more critical in turbo-charged cars than it is in normally aspirated ones, but really you should just consult your car's manual. If it says only use 95 in an emergency then do so, but if it says something like '95 minimum Octane but your car will run better on 98', then you can switch between the two.
Personally on a relatively high specific output car like a Boxster or 911, I'd stick to Super, specifically V-power, as it's got far better detergent and lubrication properties, which could prolong the life of things like injectors, and reduce carbon deposits.
Also, Octane it's nothing to do with the density of the fuel or any cobblers like that, if anything 95 has more energy content than Super, particularly Tesco 100 as it's got Alcohol in it to boost the Octane rating.
muff666 said:
Hi
i was wondering if anyone out there has tried to use normal unleaded in there porsche boxster? i have a 1998 Boxster 2.5 and was wondering if i could use normal unleaded??
Many thanks
Muff666
You could, but you'll get less mpg and so it will cost the same, and the performance will be affected.i was wondering if anyone out there has tried to use normal unleaded in there porsche boxster? i have a 1998 Boxster 2.5 and was wondering if i could use normal unleaded??
Many thanks
Muff666
Waitforme said:
I think not ..............
Super Fuels
Many of the large petrol companies have launched 'super fuels' - petrols and diesels that have a higher research octane level. These fuels are said to increase power in many vehicles, deliver less pollution than regular fuels and help to maintain a cleaner engine. Amongst these 'super fuels' are Tesco's Super Unleaded 99 Octane petrol, supplied by Greenergy, now sold at many stations across the UK and also BP's Ultimate 102 Unleaded which is currently the most advanced, high-performance petrol you can buy on UK forecourts.
Using Super Fuels
One of our users commented that using higher octane fuel than your engine requires actually gives no benefit and may be a waste of money. This is because virtually NO engines require 98 RON over 95, and the market for 'super' fuels seems to be based on people's misunderstanding of octane ratings and the placebo effect of filling up with 'more powerful' fuel - making motorists think their engine is running better in some way.
What do the fuel companies say then, to justify the "increased power" claims for the super grade fuels? Some companies say that while all fuels contain cleaning additives, 'super' fuels contain more or better detergents to keep the injectors cleaner than standard fuel. Others say the fuel is a few percent denser which gives slightly more power per litre. These benefits may be marginal though in comparison to the extra cost involved so it is worth ensuring that your engine will actually benefit before filling up.
Some engines actually do need higher octane fuel, such as race engines with very high compression and some turbocharged engines, such as the import version of the Nissan Skyline. Also, a few vehicles, such as the new BMW K1200R motorbike, can sense knock and adjust their engine tuning to take advantage of higher grade fuels. Another user commented that the 2004 BMW 330 also does this, according to the driver's handbook it makes 231 BHP on 98 octane and 221 BHP on 95. This ability is apparently widespread amongst German performance cars using Bosch / Siemens electronic engine controls.
For further information on the major fuel companies fuel options see their individual information pages:
There's a lot of opinion on there and no actual research, and it's old info - BP no longer do 102 octane fuel - when they stopped it Silverstone circuit had to get someone else to formulate something for their filling station.Super Fuels
Many of the large petrol companies have launched 'super fuels' - petrols and diesels that have a higher research octane level. These fuels are said to increase power in many vehicles, deliver less pollution than regular fuels and help to maintain a cleaner engine. Amongst these 'super fuels' are Tesco's Super Unleaded 99 Octane petrol, supplied by Greenergy, now sold at many stations across the UK and also BP's Ultimate 102 Unleaded which is currently the most advanced, high-performance petrol you can buy on UK forecourts.
Using Super Fuels
One of our users commented that using higher octane fuel than your engine requires actually gives no benefit and may be a waste of money. This is because virtually NO engines require 98 RON over 95, and the market for 'super' fuels seems to be based on people's misunderstanding of octane ratings and the placebo effect of filling up with 'more powerful' fuel - making motorists think their engine is running better in some way.
What do the fuel companies say then, to justify the "increased power" claims for the super grade fuels? Some companies say that while all fuels contain cleaning additives, 'super' fuels contain more or better detergents to keep the injectors cleaner than standard fuel. Others say the fuel is a few percent denser which gives slightly more power per litre. These benefits may be marginal though in comparison to the extra cost involved so it is worth ensuring that your engine will actually benefit before filling up.
Some engines actually do need higher octane fuel, such as race engines with very high compression and some turbocharged engines, such as the import version of the Nissan Skyline. Also, a few vehicles, such as the new BMW K1200R motorbike, can sense knock and adjust their engine tuning to take advantage of higher grade fuels. Another user commented that the 2004 BMW 330 also does this, according to the driver's handbook it makes 231 BHP on 98 octane and 221 BHP on 95. This ability is apparently widespread amongst German performance cars using Bosch / Siemens electronic engine controls.
For further information on the major fuel companies fuel options see their individual information pages:
The best answer is to do your own research - you could go the trouble of doing rolling road runs on each type of fuel and check the differnt power output readings but the simpler thing for normal road driving is to calculate your genuine mpg on 2 or 3 tankfulls of normal and the same for super (use the same brand for consistency though - BP is 97, Shell is 99 and others may be in between) and see what difference you find - I expect you'll see the economy is improved on the higher rated fuel (partly off-setting the increased cost), besides any performance improvement you may feel through your bum-dyno.
Bear in mind that 'Tesco Momentum' is one of Thorney's sponsors when reading this to give a little balance!
http://www.thorneymotorsport.co.uk/tuning/October_...
I in my last 3 cars (2 turbos & a supercharged car) I have always noticed a difference on 99ron, never fill with anything other than V-Power or Momentum
http://www.thorneymotorsport.co.uk/tuning/October_...
I in my last 3 cars (2 turbos & a supercharged car) I have always noticed a difference on 99ron, never fill with anything other than V-Power or Momentum
This is perhaps more relevant:
http://www.thorneymotorsport.co.uk/tuning/Fuel_Tes...
The CSL was in similar level of tune to Porsche N/A engines and ran a similar Siemens ECU to current generation Porsches. The difference here between 95 and 99-RON was over 40 BHP! If there is a similar percentage difference between fuels when used in Porsches, then this is a hell of a lot of free BHP - tuners of N/A engines would kill to get these kinds of increases simply, effectively and repeatably from all their bolt-on bits!
Also bear in mind that the better quality fuel will pay for itself in better fuel economy. An engine runs less efficiently if the fuel it's burning is too low octane. Reasons: the ECU pulls timing and richens the mixture to prevent detonation when cheap fuel is used. Consequences? a) Less of the heat energy produced by burning the mixture is converted to kinetic because the ignition timing is late to prevent detonation. b) The mixture has a higher percentage fuel content so more fuel is consumed per 'bang' for less power.
So using top-quality fuel really is a free upgrade and will reward you with extra free engine power.
Moral of the story - you have a Porsche, why would you want to run it on cr*p petrol FFS?
http://www.thorneymotorsport.co.uk/tuning/Fuel_Tes...
The CSL was in similar level of tune to Porsche N/A engines and ran a similar Siemens ECU to current generation Porsches. The difference here between 95 and 99-RON was over 40 BHP! If there is a similar percentage difference between fuels when used in Porsches, then this is a hell of a lot of free BHP - tuners of N/A engines would kill to get these kinds of increases simply, effectively and repeatably from all their bolt-on bits!
Also bear in mind that the better quality fuel will pay for itself in better fuel economy. An engine runs less efficiently if the fuel it's burning is too low octane. Reasons: the ECU pulls timing and richens the mixture to prevent detonation when cheap fuel is used. Consequences? a) Less of the heat energy produced by burning the mixture is converted to kinetic because the ignition timing is late to prevent detonation. b) The mixture has a higher percentage fuel content so more fuel is consumed per 'bang' for less power.
So using top-quality fuel really is a free upgrade and will reward you with extra free engine power.
Moral of the story - you have a Porsche, why would you want to run it on cr*p petrol FFS?
Edited by Ian_UK1 on Wednesday 24th November 14:39
I think my Cayman recommends 98 RON, but I've noticed that the majority of super is only 97 RON. If you want to abide 100% by the book then it's not just the pump you'll have to check at teh forecourt but whether you're on a forecourt that even does the octane reading you're looking for.
Me? I mix it up. I commute 350 miles a week where the marginal performance gains are irrelevant (which coincidentally is about a tankful). If out for some spirited driving with some chums then I may make sure my last fill is super but suspect my regular stations are only 97 anyway.
Me? I mix it up. I commute 350 miles a week where the marginal performance gains are irrelevant (which coincidentally is about a tankful). If out for some spirited driving with some chums then I may make sure my last fill is super but suspect my regular stations are only 97 anyway.
Ian_UK1 said:
This is perhaps more relevant:
http://www.thorneymotorsport.co.uk/tuning/Fuel_Tes...
The CSL was in similar level of tune to Porsche N/A engines and ran a similar Siemens ECU to current generation Porsches. The difference here between 95 and 99-RON was over 40 BHP! If there is a similar percentage difference between fuels when used in Porsches, then this is a hell of a lot of free BHP - tuners of N/A engines would kill to get these kinds of increases simply, effectively and repeatably from all their bolt-on bits!
Also bear in mind that the better quality fuel will pay for itself in better fuel economy. An engine runs less efficiently if the fuel it's burning is too low octane. Reasons: the ECU pulls timing and richens the mixture to prevent detonation when cheap fuel is used. Consequences? a) Less of the heat energy produced by burning the mixture is converted to kinetic because the ignition timing is late to prevent detonation. b) The mixture has a higher percentage fuel content so more fuel is consumed per 'bang' for less power.
So using top-quality fuel really is a free upgrade and will reward you with extra free engine power.
Moral of the story - you have a Porsche, why would you want to run it on cr*p petrol FFS?
(slight hi-jack - sorry OP)http://www.thorneymotorsport.co.uk/tuning/Fuel_Tes...
The CSL was in similar level of tune to Porsche N/A engines and ran a similar Siemens ECU to current generation Porsches. The difference here between 95 and 99-RON was over 40 BHP! If there is a similar percentage difference between fuels when used in Porsches, then this is a hell of a lot of free BHP - tuners of N/A engines would kill to get these kinds of increases simply, effectively and repeatably from all their bolt-on bits!
Also bear in mind that the better quality fuel will pay for itself in better fuel economy. An engine runs less efficiently if the fuel it's burning is too low octane. Reasons: the ECU pulls timing and richens the mixture to prevent detonation when cheap fuel is used. Consequences? a) Less of the heat energy produced by burning the mixture is converted to kinetic because the ignition timing is late to prevent detonation. b) The mixture has a higher percentage fuel content so more fuel is consumed per 'bang' for less power.
So using top-quality fuel really is a free upgrade and will reward you with extra free engine power.
Moral of the story - you have a Porsche, why would you want to run it on cr*p petrol FFS?
Edited by Ian_UK1 on Wednesday 24th November 14:39
I have asked this question before but I am not sure that I got a definitive answer......would a 1990 964 'understand' the difference between regular or premium fuel in an electronic way OR will it just provide more power from the premium as thats what the fuel is designed to do OR (as I think one person mentioned) are the brains in the car not advanced enough to compute that it is imbibing a better fuel and no difference is found?
Steve Devaney said:
Ian_UK1 said:
This is perhaps more relevant:
http://www.thorneymotorsport.co.uk/tuning/Fuel_Tes...
The CSL was in similar level of tune to Porsche N/A engines and ran a similar Siemens ECU to current generation Porsches. The difference here between 95 and 99-RON was over 40 BHP! If there is a similar percentage difference between fuels when used in Porsches, then this is a hell of a lot of free BHP - tuners of N/A engines would kill to get these kinds of increases simply, effectively and repeatably from all their bolt-on bits!
Also bear in mind that the better quality fuel will pay for itself in better fuel economy. An engine runs less efficiently if the fuel it's burning is too low octane. Reasons: the ECU pulls timing and richens the mixture to prevent detonation when cheap fuel is used. Consequences? a) Less of the heat energy produced by burning the mixture is converted to kinetic because the ignition timing is late to prevent detonation. b) The mixture has a higher percentage fuel content so more fuel is consumed per 'bang' for less power.
So using top-quality fuel really is a free upgrade and will reward you with extra free engine power.
Moral of the story - you have a Porsche, why would you want to run it on cr*p petrol FFS?
(slight hi-jack - sorry OP)http://www.thorneymotorsport.co.uk/tuning/Fuel_Tes...
The CSL was in similar level of tune to Porsche N/A engines and ran a similar Siemens ECU to current generation Porsches. The difference here between 95 and 99-RON was over 40 BHP! If there is a similar percentage difference between fuels when used in Porsches, then this is a hell of a lot of free BHP - tuners of N/A engines would kill to get these kinds of increases simply, effectively and repeatably from all their bolt-on bits!
Also bear in mind that the better quality fuel will pay for itself in better fuel economy. An engine runs less efficiently if the fuel it's burning is too low octane. Reasons: the ECU pulls timing and richens the mixture to prevent detonation when cheap fuel is used. Consequences? a) Less of the heat energy produced by burning the mixture is converted to kinetic because the ignition timing is late to prevent detonation. b) The mixture has a higher percentage fuel content so more fuel is consumed per 'bang' for less power.
So using top-quality fuel really is a free upgrade and will reward you with extra free engine power.
Moral of the story - you have a Porsche, why would you want to run it on cr*p petrol FFS?
Edited by Ian_UK1 on Wednesday 24th November 14:39
I have asked this question before but I am not sure that I got a definitive answer......would a 1990 964 'understand' the difference between regular or premium fuel in an electronic way OR will it just provide more power from the premium as thats what the fuel is designed to do OR (as I think one person mentioned) are the brains in the car not advanced enough to compute that it is imbibing a better fuel and no difference is found?
Ian
Edited by Ian_UK1 on Wednesday 24th November 15:19
I used to run my 02 Boxster S on ordinary fuel as advised by the dealer - on the odd occasions I put super in it there was absolutely no discernible difference. The dealer said that there might possibly be a detectable diffence if you actually tested it but on the road you would not notice anything at all - and the detergents etc are just the same. Had the car for two years, recently saw the next owner and it's still going strong so, by all means convince yourself you're doing the engine a favour, but I doubt very much that you are spending wisely!
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