87 octane vs. 91 octane
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From: carmel valley, ca, usa
87 octane vs. 91 octane
anybody actually know the hp/tq difference between these fuels?
i've always run 87(cheap bastard) but is there really a difference, like a couple of hp or something or better mpg
i've always run 87(cheap bastard) but is there really a difference, like a couple of hp or something or better mpg
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From: Cali
Re: 87 octane vs. 91 octane (Padawan)
There are no hp/tq gains off of octane differences. octane differences allow the cars to do better in proformance but not just by adding it. You need to tune.
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From: boostinds, WI, USA
Re: 87 octane vs. 91 octane (Luserkid)
there was a huge thread on this like 3 pages long, and it went no where, people just syaing what they ran and its better for the motor and that was it, no real answer was reached,
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From: The Hudson
Re: 87 octane vs. 91 octane (tuck'd98)
Octane rating is just the resistance to detonation, and will not yeild any gain in HP or torque for most pourposes. In a high performance or tuned engine, it can, because it needs higher octane to run properly. Run what it says to run in your manual.
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From: ft worth, tx, usa
Re: 87 octane vs. 91 octane (AutoXer)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AutoXer »</TD></TR><TR><TD CLASS="quote">Octane rating is just the resistance to detonation, and will not yeild any gain in HP or torque for most pourposes. In a high performance or tuned engine, it can, because it needs higher octane to run properly. Run what it says to run in your manual.
</TD></TR></TABLE> ding ding ding. Hi compression/ boosted motors more likely to spontaneously detonate. The higher the octane level ,the cooler the fuel will be and decreases the chanced of detonation. Only helps really when ur racing or punching it. I learned this of the discovery channel.
</TD></TR></TABLE> ding ding ding. Hi compression/ boosted motors more likely to spontaneously detonate. The higher the octane level ,the cooler the fuel will be and decreases the chanced of detonation. Only helps really when ur racing or punching it. I learned this of the discovery channel.
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From: Ben Lomond, Ca, USA
Re: 87 octane vs. 91 octane (egzboy)
I know this topic has been brought up a thousand times and probably will be brought up another thousand time, but hey, that's what a discussion board is for right? Here is my 2 cents:
The AKI (Anti-Knock Index), also known as 'Octane', is a measure of a fuels resistance to detonation as measured under controlled conditions in two separate tests run on the same type of test rig. That test rig is called a CFR (Cooperative Fuels Research) engine and the only company that make it is the Waukesha Engine Division of Dresser Industries. It is a one cylinder, variable compression engine. When a sample of fuel is being tested the engine is run with tighly controlled intake air temp, coolant temp, etc. The compression is raised until incipient knock (that crackling you sometimes hear) is detected. Next a mixture of iso-octane (2,2,4 - trimethyl pentane) and normal heptane (n-Heptane) is run in the engine. The mixture is adjusted until the engine reaches incipient knock at a level the same as the test gasoline. The proportion of the iso-octane to heptane is the octane number. For example if there were 87% iso-octane and 13% heptane in the reference fuel the octane would be 87 (You can see why people call it the Octane number).
As I said there are two different tests meant to duplicate two different driving conditions. One is called the 'Motor' test and it is more aggressive meaning the intake air temp is higher, spark is more advanced, etc. The second test is the 'Research' method. It is less harsh than the Motor method.
To get the AKI of the fuel you average the two octane numbers. You will often see on the pump the formula:
R + M
_____
2
This equals the AKI. The Motor method plus the Research method octane number divided by two equals the AKI or as it is commonly refered to, the 'Octane'.
The difference between the Research and Motor octane numbers is called the 'Sensitivity'. For example, if the Motor octane number was 85 and the Research octane number was 96 the Sensitivity would be 11.
Older cars that have fixed ignition timing and are tuned for 87 octane fuel will not benefit from using 92 or whatever your state sells. If you tune it for 92 you may get a few more horspower but be careful if you do this, to much spark advance and the engine could still detonate.
Newer cars that have adaptive ignition controls can benefit from going to 92. For example my 2002 Civic Si runs on 91 (or at least thats what I put in it). If I put 87 in it I can feel the ecu pulling back the timing via feedback from the knock sensors. After about 50 miles this has gone away because the adaptive ignition has 'remembered' that I am running 87. When I put 91 back into it the ecu constantly is trying to advance the timing and when it notices that it no longer knocks under certain load/rpm combination it 'knows' that I have 91 back in the car and adapts for it. There is also a noticable drop in power if I put 87 in an empty tank. I personally did not notice a drop in gas mileage but theoretically a more efficient engine would get better gas mileage. It never seems to work out that was. The more power our cars make the more we mash the pedal to the floor.
-Scott Tucker
The AKI (Anti-Knock Index), also known as 'Octane', is a measure of a fuels resistance to detonation as measured under controlled conditions in two separate tests run on the same type of test rig. That test rig is called a CFR (Cooperative Fuels Research) engine and the only company that make it is the Waukesha Engine Division of Dresser Industries. It is a one cylinder, variable compression engine. When a sample of fuel is being tested the engine is run with tighly controlled intake air temp, coolant temp, etc. The compression is raised until incipient knock (that crackling you sometimes hear) is detected. Next a mixture of iso-octane (2,2,4 - trimethyl pentane) and normal heptane (n-Heptane) is run in the engine. The mixture is adjusted until the engine reaches incipient knock at a level the same as the test gasoline. The proportion of the iso-octane to heptane is the octane number. For example if there were 87% iso-octane and 13% heptane in the reference fuel the octane would be 87 (You can see why people call it the Octane number).
As I said there are two different tests meant to duplicate two different driving conditions. One is called the 'Motor' test and it is more aggressive meaning the intake air temp is higher, spark is more advanced, etc. The second test is the 'Research' method. It is less harsh than the Motor method.
To get the AKI of the fuel you average the two octane numbers. You will often see on the pump the formula:
R + M
_____
2
This equals the AKI. The Motor method plus the Research method octane number divided by two equals the AKI or as it is commonly refered to, the 'Octane'.
The difference between the Research and Motor octane numbers is called the 'Sensitivity'. For example, if the Motor octane number was 85 and the Research octane number was 96 the Sensitivity would be 11.
Older cars that have fixed ignition timing and are tuned for 87 octane fuel will not benefit from using 92 or whatever your state sells. If you tune it for 92 you may get a few more horspower but be careful if you do this, to much spark advance and the engine could still detonate.
Newer cars that have adaptive ignition controls can benefit from going to 92. For example my 2002 Civic Si runs on 91 (or at least thats what I put in it). If I put 87 in it I can feel the ecu pulling back the timing via feedback from the knock sensors. After about 50 miles this has gone away because the adaptive ignition has 'remembered' that I am running 87. When I put 91 back into it the ecu constantly is trying to advance the timing and when it notices that it no longer knocks under certain load/rpm combination it 'knows' that I have 91 back in the car and adapts for it. There is also a noticable drop in power if I put 87 in an empty tank. I personally did not notice a drop in gas mileage but theoretically a more efficient engine would get better gas mileage. It never seems to work out that was. The more power our cars make the more we mash the pedal to the floor.
-Scott Tucker
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From: jacksonville, fl
no running 91 in a car that is meant to run 87 will have no performance gains. you might actually lose a few mpg...and possibly power. octane fights detonation, but theres a thin line....you want you engine to burn the fuel at the closest point before detonation to achieve the best burn.
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From: San Jose, Ca, USA
Re: 87 octane vs. 91 octane (AutoEng2002Si)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AutoEng2002Si »</TD></TR><TR><TD CLASS="quote">I know this topic has been brought up a thousand times and probably will be brought up another thousand time, but hey, that's what a discussion board is for right? Here is my 2 cents:
The AKI (Anti-Knock Index), also known as 'Octane', is a measure of a fuels resistance to detonation as measured under controlled conditions in two separate tests run on the same type of test rig. That test rig is called a CFR (Cooperative Fuels Research) engine and the only company that make it is the Waukesha Engine Division of Dresser Industries. It is a one cylinder, variable compression engine. When a sample of fuel is being tested the engine is run with tighly controlled intake air temp, coolant temp, etc. The compression is raised until incipient knock (that crackling you sometimes hear) is detected. Next a mixture of iso-octane (2,2,4 - trimethyl pentane) and normal heptane (n-Heptane) is run in the engine. The mixture is adjusted until the engine reaches incipient knock at a level the same as the test gasoline. The proportion of the iso-octane to heptane is the octane number. For example if there were 87% iso-octane and 13% heptane in the reference fuel the octane would be 87 (You can see why people call it the Octane number).
As I said there are two different tests meant to duplicate two different driving conditions. One is called the 'Motor' test and it is more aggressive meaning the intake air temp is higher, spark is more advanced, etc. The second test is the 'Research' method. It is less harsh than the Motor method.
To get the AKI of the fuel you average the two octane numbers. You will often see on the pump the formula:
R + M
_____
2
This equals the AKI. The Motor method plus the Research method octane number divided by two equals the AKI or as it is commonly refered to, the 'Octane'.
The difference between the Research and Motor octane numbers is called the 'Sensitivity'. For example, if the Motor octane number was 85 and the Research octane number was 96 the Sensitivity would be 11.
Older cars that have fixed ignition timing and are tuned for 87 octane fuel will not benefit from using 92 or whatever your state sells. If you tune it for 92 you may get a few more horspower but be careful if you do this, to much spark advance and the engine could still detonate.
Newer cars that have adaptive ignition controls can benefit from going to 92. For example my 2002 Civic Si runs on 91 (or at least thats what I put in it). If I put 87 in it I can feel the ecu pulling back the timing via feedback from the knock sensors. After about 50 miles this has gone away because the adaptive ignition has 'remembered' that I am running 87. When I put 91 back into it the ecu constantly is trying to advance the timing and when it notices that it no longer knocks under certain load/rpm combination it 'knows' that I have 91 back in the car and adapts for it. There is also a noticable drop in power if I put 87 in an empty tank. I personally did not notice a drop in gas mileage but theoretically a more efficient engine would get better gas mileage. It never seems to work out that was. The more power our cars make the more we mash the pedal to the floor.
-Scott Tucker
</TD></TR></TABLE>
Scott, you are one knowledgeable man.
The AKI (Anti-Knock Index), also known as 'Octane', is a measure of a fuels resistance to detonation as measured under controlled conditions in two separate tests run on the same type of test rig. That test rig is called a CFR (Cooperative Fuels Research) engine and the only company that make it is the Waukesha Engine Division of Dresser Industries. It is a one cylinder, variable compression engine. When a sample of fuel is being tested the engine is run with tighly controlled intake air temp, coolant temp, etc. The compression is raised until incipient knock (that crackling you sometimes hear) is detected. Next a mixture of iso-octane (2,2,4 - trimethyl pentane) and normal heptane (n-Heptane) is run in the engine. The mixture is adjusted until the engine reaches incipient knock at a level the same as the test gasoline. The proportion of the iso-octane to heptane is the octane number. For example if there were 87% iso-octane and 13% heptane in the reference fuel the octane would be 87 (You can see why people call it the Octane number).
As I said there are two different tests meant to duplicate two different driving conditions. One is called the 'Motor' test and it is more aggressive meaning the intake air temp is higher, spark is more advanced, etc. The second test is the 'Research' method. It is less harsh than the Motor method.
To get the AKI of the fuel you average the two octane numbers. You will often see on the pump the formula:
R + M
_____
2
This equals the AKI. The Motor method plus the Research method octane number divided by two equals the AKI or as it is commonly refered to, the 'Octane'.
The difference between the Research and Motor octane numbers is called the 'Sensitivity'. For example, if the Motor octane number was 85 and the Research octane number was 96 the Sensitivity would be 11.
Older cars that have fixed ignition timing and are tuned for 87 octane fuel will not benefit from using 92 or whatever your state sells. If you tune it for 92 you may get a few more horspower but be careful if you do this, to much spark advance and the engine could still detonate.
Newer cars that have adaptive ignition controls can benefit from going to 92. For example my 2002 Civic Si runs on 91 (or at least thats what I put in it). If I put 87 in it I can feel the ecu pulling back the timing via feedback from the knock sensors. After about 50 miles this has gone away because the adaptive ignition has 'remembered' that I am running 87. When I put 91 back into it the ecu constantly is trying to advance the timing and when it notices that it no longer knocks under certain load/rpm combination it 'knows' that I have 91 back in the car and adapts for it. There is also a noticable drop in power if I put 87 in an empty tank. I personally did not notice a drop in gas mileage but theoretically a more efficient engine would get better gas mileage. It never seems to work out that was. The more power our cars make the more we mash the pedal to the floor.
-Scott Tucker
</TD></TR></TABLE>
Scott, you are one knowledgeable man.
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From: Ben Lomond, Ca, USA
Re: (projectTeG)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by projectTeG »</TD></TR><TR><TD CLASS="quote">no running 91 in a car that is meant to run 87 will have no performance gains. you might actually lose a few mpg...and possibly power. octane fights detonation, but theres a thin line....you want you engine to burn the fuel at the closest point before detonation to achieve the best burn.</TD></TR></TABLE>
You definately will not lose fuel mileage nor power. You are correct about wanting your 'engine to burn the fuel at the closest point before detonation to achieve the best burn', more precisely you want your compression ratio, fuel mixture, and ignition timing (and more) to be precisely adjusted to be right below the point of incipient knock. This is where engines seem to make the best power. It's kind of like a 'tighten it until it strips and then back it out a quarter turn' theory.
-Scott Tucker
You definately will not lose fuel mileage nor power. You are correct about wanting your 'engine to burn the fuel at the closest point before detonation to achieve the best burn', more precisely you want your compression ratio, fuel mixture, and ignition timing (and more) to be precisely adjusted to be right below the point of incipient knock. This is where engines seem to make the best power. It's kind of like a 'tighten it until it strips and then back it out a quarter turn' theory.
-Scott Tucker
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From: Ben Lomond, Ca, USA
Re: 87 octane vs. 91 octane (Br1anPham)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Br1anPham »</TD></TR><TR><TD CLASS="quote">
Scott, you are one knowledgeable man.</TD></TR></TABLE>
Thank you
. . . and that was off the top of my head. You should see the long version!
Scott, you are one knowledgeable man.</TD></TR></TABLE>
Thank you
. . . and that was off the top of my head. You should see the long version!
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From: jacksonville, fl
Re: 87 octane vs. 91 octane (AutoEng2002Si)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AutoEng2002Si »</TD></TR><TR><TD CLASS="quote">Thank you
. . . and that was off the top of my head. You should see the long version!</TD></TR></TABLE>
damn theres a longer version?
. . . and that was off the top of my head. You should see the long version!</TD></TR></TABLE>
damn theres a longer version?
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From: jacksonville, fl
Re: 87 octane vs. 91 octane (AutoEng2002Si)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AutoEng2002Si »</TD></TR><TR><TD CLASS="quote">I am writing a book and the chapter on gasoline is getting out of control.</TD></TR></TABLE>
damn...i need to go to school for all of this stuff
damn...i need to go to school for all of this stuff
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From: USA
If my rusty memory serves me correct, octane 87 and 91 have a difference in burning rate. Besides that, I have always thought of
octane rating is for compression purpose since a low compression motor would not compress the air and fuel together as tightly as
a high compression motor; therefore, a low compression motor will yeild lesser chance of spontaneous combustion. So using octane 87
would be fine for a low compression motor. But for a high compression motor, there will be a greater chance for spontaneous combustion and using octane 87
will cause the fuel/air mixture to burn rapidly or uneven and resulting in pinging/knocking.
octane rating is for compression purpose since a low compression motor would not compress the air and fuel together as tightly as
a high compression motor; therefore, a low compression motor will yeild lesser chance of spontaneous combustion. So using octane 87
would be fine for a low compression motor. But for a high compression motor, there will be a greater chance for spontaneous combustion and using octane 87
will cause the fuel/air mixture to burn rapidly or uneven and resulting in pinging/knocking.
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From: Ben Lomond, Ca, USA
Re: (dude_123)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dude_123 »</TD></TR><TR><TD CLASS="quote">If my rusty memory serves me correct, octane 87 and 91 have a difference in burning rate. Besides that, I have always thought of
octane rating is for compression purpose since a low compression motor would not compress the air and fuel together as tightly as
a high compression motor; therefore, a low compression motor will yeild lesser chance of spontaneous combustion. So using octane 87
would be fine for a low compression motor. But for a high compression motor, there will be a greater chance for spontaneous combustion and using octane 87
will cause the fuel/air mixture to burn rapidly or uneven and resulting in pinging/knocking.</TD></TR></TABLE>
The rate at which the air/fuel mixture burns is no different between the two (87 and 91) but the point at which the molecules of gasoline have developed into species that will auto-ignite comes sooner.
octane rating is for compression purpose since a low compression motor would not compress the air and fuel together as tightly as
a high compression motor; therefore, a low compression motor will yeild lesser chance of spontaneous combustion. So using octane 87
would be fine for a low compression motor. But for a high compression motor, there will be a greater chance for spontaneous combustion and using octane 87
will cause the fuel/air mixture to burn rapidly or uneven and resulting in pinging/knocking.</TD></TR></TABLE>
The rate at which the air/fuel mixture burns is no different between the two (87 and 91) but the point at which the molecules of gasoline have developed into species that will auto-ignite comes sooner.
OG triple OG
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From: Norcal
Re: 87 octane vs. 91 octane (turbo_b16_ex)
the higher the octane the slower it burns , which means the farther you can advance ignition timing without detonating, it also allows you to run higher boost without detonating. you dont get higher whp from higher octane , the higher octane allows you to achieve a higher whp via tuning.....
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From: Ben Lomond, Ca, USA
Re: 87 octane vs. 91 octane (Hella_JDM)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hella_JDM »</TD></TR><TR><TD CLASS="quote">the higher the octane the slower it burns , which means the farther you can advance ignition timing without detonating, it also allows you to run higher boost without detonating. you dont get higher whp from higher octane , the higher octane allows you to achieve a higher whp via tuning.....</TD></TR></TABLE>
You are correct in saying you need to advance the ignition timing to take advantage of the higher octane fuel but flame speed has very little to do with a gasoline's AKI (octane). It is the resistance of the hydrocarbon molecules in the end gases to degrade into 'species' (different types of molecules) that will auto-ignite. The molecules are being compressed (thus temperature rises) and heated by conductive and radiant heat due to the incoming flame front. If the heat and the pressure cause the end gases to reach the auto-ignition temperature, the end gases will detonate. This auto-ignition temperature is higher for high-octane fuels that low-octane fuels.
You are correct in saying you need to advance the ignition timing to take advantage of the higher octane fuel but flame speed has very little to do with a gasoline's AKI (octane). It is the resistance of the hydrocarbon molecules in the end gases to degrade into 'species' (different types of molecules) that will auto-ignite. The molecules are being compressed (thus temperature rises) and heated by conductive and radiant heat due to the incoming flame front. If the heat and the pressure cause the end gases to reach the auto-ignition temperature, the end gases will detonate. This auto-ignition temperature is higher for high-octane fuels that low-octane fuels.
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Re: 87 octane vs. 91 octane (egzboy)
Very little difference. if it runs on 87 octane, and you don't hear any pinging. that means you're alright. Most cars that are 9:1 compression artio can run on 87 octane with no problem.
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From: Charlotte, NC
Re: (AutoEng2002Si)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AutoEng2002Si »</TD></TR><TR><TD CLASS="quote">The rate at which the air/fuel mixture burns is no different between the two (87 and 91) but the point at which the molecules of gasoline have developed into species that will auto-ignite comes sooner.</TD></TR></TABLE>
What can you tell us about the difference in energy in low octane vs. higher octane fuel? We were talking about it in the shop last night, and mention was made of using the lowest octane you can, due to it containing more energy. I can see how that might be true, so long as you're not detonating when you have all the timing the motor wants to make peak BMEP. Teach us, oh wise one.
What can you tell us about the difference in energy in low octane vs. higher octane fuel? We were talking about it in the shop last night, and mention was made of using the lowest octane you can, due to it containing more energy. I can see how that might be true, so long as you're not detonating when you have all the timing the motor wants to make peak BMEP. Teach us, oh wise one.
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From: Ben Lomond, Ca, USA
Re: (drdisco69)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by drdisco69 »</TD></TR><TR><TD CLASS="quote">
What can you tell us about the difference in energy in low octane vs. higher octane fuel? We were talking about it in the shop last night, and mention was made of using the lowest octane you can, due to it containing more energy. I can see how that might be true, so long as you're not detonating when you have all the timing the motor wants to make peak BMEP. Teach us, oh wise one. </TD></TR></TABLE>
The energy content of gasoline (whether it be 87 or 91) is approximately 20,000 BTU's (British Thermal Units) per pound. 87 Octane fuel does not have more energy in it, whoever told you that was wrong. How would it be that you make more power on high octane gas then? For the most part, 87 and 91 octane contain mostly the same gasoline (meaning the hydrocarbon molecules and excluding the additives). The difference is in the additive packages that go into the base stock of gasoline. The 91 octane fuel has better knock inhibiters. The knock inhibiters work by preventing the gasoline molecules in the high pressure/temperature end gases (I don't think I defined 'end gases' before - they are all the unburnt charge ahead of the flame front) from degrading into species that will auto-ignite. Racing gasolines produce more power because you can increase the compression ratio and ignition advance if needed, thus raising the efficiency of the engine (this also means it won't give your beater any more power). This, of course, raises B.M.E.P. (Brake Mean Effective Pressure). B.M.E.P. is the average pressure in the cylinder per cycle. The higher the B.M.E.P., the more power you will make.
Here's some gasoline trivia (woo hoo!). The base stock for the gasoline in your area is probably the same no matter what brand it is. The reason for this is that the gasoline (especially in the inland states) is moved via pipeline and all the oil companies use the same ones. There is a difference between brands however. Some manufacturers cut their gasoline with ethenol (it's required here in California for some stupid ******* political reason - the enviro-hippies driving their pollution spewing VW buses lobbied for it I think) and the additive packages are different between manufacturers. They are not so different though - there are two major additive package suppliers, Chevron and ConocoPhillips and they supply the additive packages to the smaller oil companies. At least that was true a couple of years ago. So all the oil companies seem to be in bed with each other just like the rest of the automotive industry.
This information came straight from the mouth of Roy Howell, the majority stock holder and Head of Product Development (He's a Chemist) of Redline Oil Company.
If that didn't answer your question or you have another one just ask and I will try an answer it. I love a challenge.
-Scott Tucker
What can you tell us about the difference in energy in low octane vs. higher octane fuel? We were talking about it in the shop last night, and mention was made of using the lowest octane you can, due to it containing more energy. I can see how that might be true, so long as you're not detonating when you have all the timing the motor wants to make peak BMEP. Teach us, oh wise one.
</TD></TR></TABLE>The energy content of gasoline (whether it be 87 or 91) is approximately 20,000 BTU's (British Thermal Units) per pound. 87 Octane fuel does not have more energy in it, whoever told you that was wrong. How would it be that you make more power on high octane gas then? For the most part, 87 and 91 octane contain mostly the same gasoline (meaning the hydrocarbon molecules and excluding the additives). The difference is in the additive packages that go into the base stock of gasoline. The 91 octane fuel has better knock inhibiters. The knock inhibiters work by preventing the gasoline molecules in the high pressure/temperature end gases (I don't think I defined 'end gases' before - they are all the unburnt charge ahead of the flame front) from degrading into species that will auto-ignite. Racing gasolines produce more power because you can increase the compression ratio and ignition advance if needed, thus raising the efficiency of the engine (this also means it won't give your beater any more power). This, of course, raises B.M.E.P. (Brake Mean Effective Pressure). B.M.E.P. is the average pressure in the cylinder per cycle. The higher the B.M.E.P., the more power you will make.
Here's some gasoline trivia (woo hoo!). The base stock for the gasoline in your area is probably the same no matter what brand it is. The reason for this is that the gasoline (especially in the inland states) is moved via pipeline and all the oil companies use the same ones. There is a difference between brands however. Some manufacturers cut their gasoline with ethenol (it's required here in California for some stupid ******* political reason - the enviro-hippies driving their pollution spewing VW buses lobbied for it I think) and the additive packages are different between manufacturers. They are not so different though - there are two major additive package suppliers, Chevron and ConocoPhillips and they supply the additive packages to the smaller oil companies. At least that was true a couple of years ago. So all the oil companies seem to be in bed with each other just like the rest of the automotive industry.
This information came straight from the mouth of Roy Howell, the majority stock holder and Head of Product Development (He's a Chemist) of Redline Oil Company.
If that didn't answer your question or you have another one just ask and I will try an answer it. I love a challenge.
-Scott Tucker
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Re: (AutoEng2002Si)
Wow Scott, I worker at a Conoco Phillips refinery for many years, and I didn't know that. I declare Scott Tucker the man to go to if anybody has any question about various gasoline octanes.
Nice post Scott.....
Nice post Scott.....
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From: Ben Lomond, Ca, USA
Re: (hazw8st)
Roy Howell (as I mentioned head of product development for Redline) use to work for Phillips before moving to Redline a long time ago. He's a really cool guy who just likes talking about oil, anybodys oil. He said in a lecture, "Mobil 1 is good for your daily driver cause it's usually on sale and it's good stuff. Whatever you do, just use synthetic, that's all I ask."