Autogas for GA
Thread Starter
Autogas for GA
The new Piper website list one of their Archers did a 2,000nm round the US using 93 octane motor fuel. A similar spec to the 93UL that's coming.
I know theres a few Lycomming 320 & 360 engines that are certified for mogas. But what is "mogas". Is it from a specialist refinery or do you just call BP and order 100,000 litres of BP Ultimate.
What other things would have to be considered if a flying school wanted to go mogas.........apart from STC's. Can you mix mogas with regular 100LL. At a guess you would save 50 cents a litre and using 100,000 litres a month is not small change.
I know theres a few Lycomming 320 & 360 engines that are certified for mogas. But what is "mogas". Is it from a specialist refinery or do you just call BP and order 100,000 litres of BP Ultimate.
What other things would have to be considered if a flying school wanted to go mogas.........apart from STC's. Can you mix mogas with regular 100LL. At a guess you would save 50 cents a litre and using 100,000 litres a month is not small change.
Here you go:
I think most of these were done before 98 Octane and most apply to engines designed for 80/87 Avgas, so 91 Octane is adequate.
MOGAS is out of the pump from your local service station, but ethanol is a no-no. So you should stick with a branded high volume site and run an ethanol test.
I think most of these were done before 98 Octane and most apply to engines designed for 80/87 Avgas, so 91 Octane is adequate.
MOGAS is out of the pump from your local service station, but ethanol is a no-no. So you should stick with a branded high volume site and run an ethanol test.
Thread Starter
Thanks Akro,
Very interesting website. Interestingly no fuel injected models seem to be listed. Is there an inherent problem with the stoneage injection systems with running mogas?
Also, pump gas at the average servo is something like 50% tax, applicable to road users. Farmers are able to claim a diesel rebate for vehicles that don't use public roads.....I'm quite sure an aircraft wouldn't use a public road
So I need to find a way to buy large amounts of fuel without the road tax component.
Very interesting website. Interestingly no fuel injected models seem to be listed. Is there an inherent problem with the stoneage injection systems with running mogas?
Also, pump gas at the average servo is something like 50% tax, applicable to road users. Farmers are able to claim a diesel rebate for vehicles that don't use public roads.....I'm quite sure an aircraft wouldn't use a public road
So I need to find a way to buy large amounts of fuel without the road tax component.
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WARNING
93AKI is equivalent to our RON 98 in other words BP98 or Caltex Vortex 98 and NOTHING LESS.
DO NOT GET CONFUSED.
The other problem is that mogas of the lesser grades has all sorts of compounds in it, and the amount of olefins in it can be a serious problem. Ask me how quick I can remove, clean and refit 3 x carbies on my near new V6 Yamaha outboard. Yes 2hours! Lost of practise, all from gum deposits (olefins) and usually I use Caltex 98 except on odd occasions.
So is it worth it? In my opinion no way.
The piper story is about a dedicated "Aviation grade auto gas" and if you think every FBO in Australia or the USA is going to stock such a thing and a 100 MON grade with both at a reasonable price.....think again.
Hang in there with 100LL for just a little longer until the G100UL is available.
Any questions fire away, happy to help as best I can.
PS: Typical min spec 100LL is about 101.5MON in order to get the 130 Rich mixture rating, can be a little less but basically to compare that to the AKI ratings it would be 106.
93AKI is equivalent to our RON 98 in other words BP98 or Caltex Vortex 98 and NOTHING LESS.
DO NOT GET CONFUSED.
The other problem is that mogas of the lesser grades has all sorts of compounds in it, and the amount of olefins in it can be a serious problem. Ask me how quick I can remove, clean and refit 3 x carbies on my near new V6 Yamaha outboard. Yes 2hours! Lost of practise, all from gum deposits (olefins) and usually I use Caltex 98 except on odd occasions.
So is it worth it? In my opinion no way.
The piper story is about a dedicated "Aviation grade auto gas" and if you think every FBO in Australia or the USA is going to stock such a thing and a 100 MON grade with both at a reasonable price.....think again.
Hang in there with 100LL for just a little longer until the G100UL is available.
Any questions fire away, happy to help as best I can.
PS: Typical min spec 100LL is about 101.5MON in order to get the 130 Rich mixture rating, can be a little less but basically to compare that to the AKI ratings it would be 106.
Last edited by Jabawocky; 31st Oct 2013 at 08:17.
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Is there an inherent problem with the stoneage injection systems with running mogas?
Check PM's for a phone number to call
Anyone else wanting to learn a bit about this topic, I will devote a small amount of time over and above the normal APS Engine Management Made Easy course content to answer questions and discuss what is and is not possible and happening in the industry, and I can do that far better than a post on the internet. Only a few seats available.
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Ok, I'll bite...
Jaba,
Long time viewer of fuel replacement threads, first time poster on the subject...
Genuine questions, and I don't mean to sound flip about it, if that how it comes out....
Question the first - When? Precious little other than 'soon'. Even if approval etc were issued tomorrow and everyone said, yes, it's fine, use it, you'd think there'd be 12-18 months at least before I was able to feed my TSIO-360KB and it's brother just that diet!?
Question the second - Vapour pressure. Mogas of any flavour has awful vapour pressure properties, compared to AvGas. Will G100UL suffer from this? The engines that are glued to my draggy airframe much prefer being up high and passing the workload off to the turbos!
And please correct me if I'm wrong, but doesn't some premium fuels (98RON) still have an ethanol content?
Long time viewer of fuel replacement threads, first time poster on the subject...
Genuine questions, and I don't mean to sound flip about it, if that how it comes out....
Question the first - When? Precious little other than 'soon'. Even if approval etc were issued tomorrow and everyone said, yes, it's fine, use it, you'd think there'd be 12-18 months at least before I was able to feed my TSIO-360KB and it's brother just that diet!?
Question the second - Vapour pressure. Mogas of any flavour has awful vapour pressure properties, compared to AvGas. Will G100UL suffer from this? The engines that are glued to my draggy airframe much prefer being up high and passing the workload off to the turbos!
And please correct me if I'm wrong, but doesn't some premium fuels (98RON) still have an ethanol content?
From the Autofuels website FAQ
It seems they tried a whole range of aircraft and only obtained STC's on those which ran well without modification. I think many others could be converted easily (technically), but might be difficult in a regulatory sense. By this I mean that getting the sort of fuel pumps you want that are TSO approved and then getting the plumbing changes approved might just be a bridge too far.
I THINK that if you look at the CAFE foundations early work you might see some research on MOGAS too.
A thing about fuel is that we import lots of it, most of which is bought on the spot market in Singapore. Fuel imported in that way can be a lottery. In Australia, 91 octane is refined by: Shell, Mobil, BP & Caltex, although Caltex will cease soon. 98 octane is refined by BP, Shell & Mobil. If you buy 98 octane from anyone else its source is uncertain. The inground tanks from which the fuel is dispensed is also an issue. Old ones take in water and contaminants. The new fibreglass ones are best. Which is why I think its best to buy from a high volume BP, Shell or Mobil site.
Australian fuel improved dramatically about 8 years ago when (for the first time) we introduced National fuel standards. You can download fuel Technical data sheets from the fuel companies & the govt fuel standards web sites. In the old days we needed to import batches of fuel for European vehicles because our fuel was inadequate (mainly due to sulfur content)
Fuel also varies in formulation a number of times throughout the year depending on where you are in Australia. Different companies use different schedules. Its primarily about ease of starting. We sometimes have special batches of Winter European fuel refined for vehicle testing here. Among western countries, country to country differences are mainly about vapour pressures. Although I've had to research fuel in Afghanistan and the peculiar Indonesian 88 fuel, both of which are entertaining. If you were really fussy, you'd try and buy summer formulation for aircraft because of its higher vapour pressure.
Octane rating is a bit of a minefield. There are 4 or 5 different ratings. Octane rating is still pretty much determined in the same manner that was created by Sir Harry Ricardo in the early 1900's. This is basically to use a single cylinder engine and increase the compression ratio until it "knocks". This point can be influenced by mixture, which in simple terms leads to the difference in ratings. AVGAS & road fuel use different ratings. Most of the MOGAS STC's are based on 87 or 88 AKI fuel with some of the higher compression ratio engines requiring 91 AKI fuel. So, most are likely to be OK on Aussie 91 Octane.
Its also worth noting that in Australia the published octane rating is a minimum. Fuel from the pump is frequently higher (esp 91 octane).
Personally, I would use 98 octane because its specifications are tighter and I think (without justification) that you are less likely to get a shandy of fuel or traces of toluene, ethanol and other (illegal) cheapening agents. BP 98 Octane fuel is sporadically exported to California. We make pretty good fuel here now.
And for Jabba, I'd be questioning where he buys the fuel for the boat more than the fuel itself. The fuel from some country stations which still have old cast iron tanks can be a nightmare.
We do not have Auto Fuel STCs for engines using Bendix fuel injection because it failed our flight testing. Continental fuel injection did not have that problem and is therefore approved – I0-470-J or -K (225hp). The 260hp I0-470 and 285hp I0-520 are also approved. These last two require Anti Detonation Injection (ADI).
I THINK that if you look at the CAFE foundations early work you might see some research on MOGAS too.
A thing about fuel is that we import lots of it, most of which is bought on the spot market in Singapore. Fuel imported in that way can be a lottery. In Australia, 91 octane is refined by: Shell, Mobil, BP & Caltex, although Caltex will cease soon. 98 octane is refined by BP, Shell & Mobil. If you buy 98 octane from anyone else its source is uncertain. The inground tanks from which the fuel is dispensed is also an issue. Old ones take in water and contaminants. The new fibreglass ones are best. Which is why I think its best to buy from a high volume BP, Shell or Mobil site.
Australian fuel improved dramatically about 8 years ago when (for the first time) we introduced National fuel standards. You can download fuel Technical data sheets from the fuel companies & the govt fuel standards web sites. In the old days we needed to import batches of fuel for European vehicles because our fuel was inadequate (mainly due to sulfur content)
Fuel also varies in formulation a number of times throughout the year depending on where you are in Australia. Different companies use different schedules. Its primarily about ease of starting. We sometimes have special batches of Winter European fuel refined for vehicle testing here. Among western countries, country to country differences are mainly about vapour pressures. Although I've had to research fuel in Afghanistan and the peculiar Indonesian 88 fuel, both of which are entertaining. If you were really fussy, you'd try and buy summer formulation for aircraft because of its higher vapour pressure.
Octane rating is a bit of a minefield. There are 4 or 5 different ratings. Octane rating is still pretty much determined in the same manner that was created by Sir Harry Ricardo in the early 1900's. This is basically to use a single cylinder engine and increase the compression ratio until it "knocks". This point can be influenced by mixture, which in simple terms leads to the difference in ratings. AVGAS & road fuel use different ratings. Most of the MOGAS STC's are based on 87 or 88 AKI fuel with some of the higher compression ratio engines requiring 91 AKI fuel. So, most are likely to be OK on Aussie 91 Octane.
Its also worth noting that in Australia the published octane rating is a minimum. Fuel from the pump is frequently higher (esp 91 octane).
Personally, I would use 98 octane because its specifications are tighter and I think (without justification) that you are less likely to get a shandy of fuel or traces of toluene, ethanol and other (illegal) cheapening agents. BP 98 Octane fuel is sporadically exported to California. We make pretty good fuel here now.
And for Jabba, I'd be questioning where he buys the fuel for the boat more than the fuel itself. The fuel from some country stations which still have old cast iron tanks can be a nightmare.
but doesn't some premium fuels (98RON) still have an ethanol content?
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Akro....fuel purchased around the Brisbane area, but at times 98 has not been available. 
I have very good friends who tweek the knobs and dials at two major refineries in Australia, if they had surplus strawberry jam in the refinery and could stick that in the 91 ULP......THEY WOULD!
Even with the Aussie fuel standards, the spec is very broad.
I have very good friends who tweek the knobs and dials at two major refineries in Australia, if they had surplus strawberry jam in the refinery and could stick that in the 91 ULP......THEY WOULD!
Even with the Aussie fuel standards, the spec is very broad.
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RatsoreA, hope these do the questions justice, no need to bite though!
Jaba,
Long time viewer of fuel replacement threads, first time poster on the subject...
Genuine questions, and I don't mean to sound flip about it, if that how it comes out....
Question the first - When? Precious little other than 'soon'. Even if approval etc were issued tomorrow and everyone said, yes, it's fine, use it, you'd think there'd be 12-18 months at least before I was able to feed my TSIO-360KB and it's brother just that diet!? Well there is a time frame that depends on regulation or just commercial pressure. Of course if Innospec went broke, had a massive industrial accident, change would be faster, but in the case of the likely candidate UL fuel, the changeover for a refinery is not hard or complex and could be done in 6-12 months. What happens here will depend on what happens in the USA.
Question the second - Vapour pressure. Mogas of any flavour has awful vapour pressure properties, compared to AvGas. YESWill G100UL suffer from this?No not at all. The spec for G100UL is identical to Avgas. The engines that are glued to my draggy airframe much prefer being up high and passing the workload off to the turbos!
And please correct me if I'm wrong, but doesn't some premium fuels (98RON) still have an ethanol content? Not that I am aware of, or certainly the BP98 does not. Tiny amounts of Alcohol is useful in avgas or G100UL for that matter, but it is tiny amounts for specific uses.
You will have much better engine health as a result
Long time viewer of fuel replacement threads, first time poster on the subject...
Genuine questions, and I don't mean to sound flip about it, if that how it comes out....
Question the first - When? Precious little other than 'soon'. Even if approval etc were issued tomorrow and everyone said, yes, it's fine, use it, you'd think there'd be 12-18 months at least before I was able to feed my TSIO-360KB and it's brother just that diet!? Well there is a time frame that depends on regulation or just commercial pressure. Of course if Innospec went broke, had a massive industrial accident, change would be faster, but in the case of the likely candidate UL fuel, the changeover for a refinery is not hard or complex and could be done in 6-12 months. What happens here will depend on what happens in the USA.
Question the second - Vapour pressure. Mogas of any flavour has awful vapour pressure properties, compared to AvGas. YESWill G100UL suffer from this?No not at all. The spec for G100UL is identical to Avgas. The engines that are glued to my draggy airframe much prefer being up high and passing the workload off to the turbos!
And please correct me if I'm wrong, but doesn't some premium fuels (98RON) still have an ethanol content? Not that I am aware of, or certainly the BP98 does not. Tiny amounts of Alcohol is useful in avgas or G100UL for that matter, but it is tiny amounts for specific uses.
You will have much better engine health as a result
Akro....fuel purchased around the Brisbane area, but at times 98 has not been available.
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Akro, I suspect it is BP from Bulwer Island. Caltex in Brisbane have a refinery but I doubt they produce it.
You did ask where I was buying it.....not who I thought was making it. And truly that could be from anywhere even with the majors. Shell shipped 98RON from their now closed Clyde refinery up here not that long ago.
And hence the trouble with mogas in aircraft, you just can't be sure and there is no requirement to give you surety.
You did ask where I was buying it.....not who I thought was making it. And truly that could be from anywhere even with the majors. Shell shipped 98RON from their now closed Clyde refinery up here not that long ago.
And hence the trouble with mogas in aircraft, you just can't be sure and there is no requirement to give you surety.
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IMO, any replacement fuel that requires that high performance engines be altered or modified to successfully use it is dooming the GA fleet. It must be a drop-in replacement. GA cannot withstand that kind of expenditure for no gain.
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Water injection on a CE-402, that'll be interesting.
As I understand it they are not able to be used for part 135 operations anyway.
My comments on another thread;
What is critical besides the required performance parameters and material compatibility is that you can swap from one to the other and blend them in any ratio in the wing or the FBO tanks. Anything else than complete 'blendability' with existing 100LL is not going to work for the period of time it takes to change over. This is no easy task, and if it was easy, it would have been done long ago.
In summary any replacement for 100LL needs to be;
1. MON99.6 and supercharge rich rating of 130, or higher.
2. RVP of 5.5-7.1 PSI
3. Must not require modification to the aircraft/engine (read certification)
4. Must not have a derating of HP, most twins would be grounded if so
5. Needs to produced in sufficient volume to be rolled out across the USA, Canada, Brazil, Australia, Europe etc.
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Not bad articles, except the old wives tails 
Then to contradict the statements above
I wonder why that is? Could it be no lead thus no deposits that are abrasive.
Folks when reading these articles remember not to become part of the OWT's that have almost been killed off, but seem to resurface far too often!
Lead is also used to provide lubrication of upper cylinder components such as valves, pistons, cylinder walls and valve guides.
Lastly, we emphasized the im- portance of having updated valve train components in any engine in which autogas was going to be burned. Modern valves, guides and seats are more tolerant of the absence of lead so that they will not burn up prematurely.
engine manufacturers have identified high upper cylinder and valve wear as a problem when unleaded fuel is used during the break-in process.
When an engine cylinder is repaired or overhauled, an owner should be certain that the latest style, high quality valves, compat- ible valve guides and valve seats are installed that are designed for use with 100LL fuel. As an additional benefit of the new hardware, the valve train is more tolerant of unleaded fuel use.
After repairs to cylinders are ac- complished such as grinding valve seats, valve refacing, or installing replacement parts such as valve guides, it is important to break in these new parts for approximately 25 hours with leaded fuel to provide some lubrication before using lead-free fuel.
After repairs to cylinders are ac- complished such as grinding valve seats, valve refacing, or installing replacement parts such as valve guides, it is important to break in these new parts for approximately 25 hours with leaded fuel to provide some lubrication before using lead-free fuel.
This fuel has been approved for use with certain models of Lycoming engines (including engines that originally used 91/96 octane avgas) and is now being used in certified aircraft in Sweden.
The recent unleaded avgas operations with this specific unleaded fuel have been very promising with up-per cylinder and valve wear. It is important to differentiate this fuel from automotive fuel.
The recent unleaded avgas operations with this specific unleaded fuel have been very promising with up-per cylinder and valve wear. It is important to differentiate this fuel from automotive fuel.
Folks when reading these articles remember not to become part of the OWT's that have almost been killed off, but seem to resurface far too often!
Last edited by Jabawocky; 2nd Nov 2013 at 00:02.
I'm sorry, I don't mean to be difficult, but if we are going to dismiss OWT's, lets do it with proper peer reviewed technical papers.
This is probably the best:
Valve Problems with Lead Free Gasoline
Influence of Low Lead Fuels on Exhaust Valve Performance
But if you don't want to pay the SAE money, here are some others:
http://www.unep.org/transport/pcfv/p...FinalDraft.pdf
http://www.martinwellsco.com/skin/fr...udyReprint.pdf
http://www.diva-portal.org/smash/get...FULLTEXT01.pdf
p13 of the final reference says
The conclusion from all of these is that lead plays a role in creating a coating on the valve seat which reduces wear which in turn is evident as valve recession. This is not evident in road vehicles because of advances in the design of valve seat profiles and valve seat materials. Valves rotate at about 360 deg every 3-5 seconds. These features are (I think) incorporated in some aircraft engines, but not all. One of the problems of aircraft engines is that there hasn't been significant design iterations since the 1960's when this issue was first being understood. By comparison there have probably been 10 design iteration of automotive engines in that time. My 1972 Alfa Montreal incorporates hardened valve seats which means that it happily runs on unleaded fuel. Changing to unleaded fuel for vehicles has not been such an issue because the valve design is so much better in modern cars than aircraft.
I do understand that many aircraft engine manufacturers have changed the design of valve inserts to make them more tolerate of low lead / lead free fuels, which is probably the missing link between the 2 statements that you think are contradictory.
This is probably the best:
Valve Problems with Lead Free Gasoline
Influence of Low Lead Fuels on Exhaust Valve Performance
But if you don't want to pay the SAE money, here are some others:
http://www.unep.org/transport/pcfv/p...FinalDraft.pdf
http://www.martinwellsco.com/skin/fr...udyReprint.pdf
http://www.diva-portal.org/smash/get...FULLTEXT01.pdf
p13 of the final reference says
By removing lead from
the fuels in order to facilitate catalytic converters and reducing atmospheric
lead pollution, the beneficial tribofilms from the lead component was removed
and the wear of some critical engine components accelerated dramatically
[4,5].
the fuels in order to facilitate catalytic converters and reducing atmospheric
lead pollution, the beneficial tribofilms from the lead component was removed
and the wear of some critical engine components accelerated dramatically
[4,5].
I do understand that many aircraft engine manufacturers have changed the design of valve inserts to make them more tolerate of low lead / lead free fuels, which is probably the missing link between the 2 statements that you think are contradictory.
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I disagree with your conclusion Akro, the last document is the only one that even mentions it but if I were to be critical it refers far more often to oil deposits in the tribofilm. They fell for the owt themselves. Not unusual.
The other four seem to be debunking the OWTs effectively. They almost don't believe in valve recession problems at all. They do support everything Walter or myself have posted. Thank you
Time to revisit a post by Walter a few months ago. Point 6 in particular.
Lastly, the BP98 and quite likely the Caltex, comes from Bulwer Island. I was talking to my mate who actually makes it and the RON coming out tonight was 105. They will throw other junk in to get rid of it and meet the dumbed down 98. I wonder where the gum comes from even in the good stuff.
The other four seem to be debunking the OWTs effectively. They almost don't believe in valve recession problems at all. They do support everything Walter or myself have posted. Thank you
Time to revisit a post by Walter a few months ago. Point 6 in particular.
A few things that ARE in harmony with the laws of physics:
1) Lead does NOT slow the burn rate of avgas. It increases the latency, which is the time it takes for the flame front to become organized after the spark event. This is why it suppresses detonation. After the flame front is organized the flame front moves at the same speed with or without the lead.
2) The iso-octane study done by the FAA took two NEW engines, one on the right, one on the left in a twin. One engine was run on 100LL; the other on 100 octane (iso-octane) with no lead. After several hundred hours, there was NO difference in the wear patterns in the two engines. NONE. This proved that lead had no effect on wear or exhaust valve life or performance. Lead is NOT needed in ANY way to help valves. Period. Parade Rest. It is used ONLY to widen the detonation margin.
3) The reasons seats were changed in auto engines when unleaded fuel came about was that the existing seats were not hard (like aircraft engines have always had). These issues are not in any way applicable to aircraft engines.
4) 100 octane unleaded fuel performs exactly like 100LL. Why? If you remove the lead in 100LL it is not 100 octane.
5) John Deakin is right. Everything he says about this topic is in harmony with Taylor, Haywood, and all other known sources of DATA, including the most advanced engine test facility in the world.
6) Many SAE papers on the topic of the effects of lead in combustion are flawed in that the studies did not control for internal cylinder pressures (which ARE the cause of the observed problems).
7) Healthy exhaust stains are a very, very light tan (almost whitish) because this indicates that the engine is being run at BSFC(min) mixtures (LOP).
I have data to support all of the above. I have been showing it during the APS classes for over a decade to thousands of pilots, mechanics, OEM engineers and combustion engineers from the engine manufacturers. Not once has anyone taken issue with the hard data or presented any contrarian data.
If you have any contrarian data (respectfully, no opinions, please) I would deeply appreciate seeing it.
If you would like to see this data, we will be presenting it in Ada, Oklahoma in October and Sidney in November (I think it's November--can't recall at this instant).
It seems as though everyone has an opinion on this topic, but it is worth remembering that the data has no opinion. It is what it is.
1) Lead does NOT slow the burn rate of avgas. It increases the latency, which is the time it takes for the flame front to become organized after the spark event. This is why it suppresses detonation. After the flame front is organized the flame front moves at the same speed with or without the lead.
2) The iso-octane study done by the FAA took two NEW engines, one on the right, one on the left in a twin. One engine was run on 100LL; the other on 100 octane (iso-octane) with no lead. After several hundred hours, there was NO difference in the wear patterns in the two engines. NONE. This proved that lead had no effect on wear or exhaust valve life or performance. Lead is NOT needed in ANY way to help valves. Period. Parade Rest. It is used ONLY to widen the detonation margin.
3) The reasons seats were changed in auto engines when unleaded fuel came about was that the existing seats were not hard (like aircraft engines have always had). These issues are not in any way applicable to aircraft engines.
4) 100 octane unleaded fuel performs exactly like 100LL. Why? If you remove the lead in 100LL it is not 100 octane.
5) John Deakin is right. Everything he says about this topic is in harmony with Taylor, Haywood, and all other known sources of DATA, including the most advanced engine test facility in the world.
6) Many SAE papers on the topic of the effects of lead in combustion are flawed in that the studies did not control for internal cylinder pressures (which ARE the cause of the observed problems).
7) Healthy exhaust stains are a very, very light tan (almost whitish) because this indicates that the engine is being run at BSFC(min) mixtures (LOP).
I have data to support all of the above. I have been showing it during the APS classes for over a decade to thousands of pilots, mechanics, OEM engineers and combustion engineers from the engine manufacturers. Not once has anyone taken issue with the hard data or presented any contrarian data.
If you have any contrarian data (respectfully, no opinions, please) I would deeply appreciate seeing it.
If you would like to see this data, we will be presenting it in Ada, Oklahoma in October and Sidney in November (I think it's November--can't recall at this instant).
It seems as though everyone has an opinion on this topic, but it is worth remembering that the data has no opinion. It is what it is.
Lastly, the BP98 and quite likely the Caltex, comes from Bulwer Island. I was talking to my mate who actually makes it and the RON coming out tonight was 105. They will throw other junk in to get rid of it and meet the dumbed down 98. I wonder where the gum comes from
even in the good stuff.