We have access to 93 octane? I realize the bigger deal is detergent/additive pkg, but does octane and by extension 100% gasoline (no eth gas) have any bearing on Carbon buildup
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Does gasoline's octane have ANY bearing on CBU?
- Thread starter Speak2Mountain
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To answer your question on carbon buildup with 100% gas as compared to 10% ethanol gas regardless of octane...not that I am aware of!
However, there is a fuel economy benefit for 100% gasoline but, what is the delta on the paying higher prices for 100% gas as compared to just regular 87-93 octane. To me, it's all bottom line.
I have or had vehicles for 16, 18 & over 30 years and the same with lawnmower/snowblower, weedwacker/leafblower all without any fuel issues using just regular 87 octane fuel and over the past 25-30 years(that I am aware of), using 10% ethanol.
In most areas that I am aware of, 100% gas is only the highest octane gas at a filling station. All other lower octane gasoline is 10% ethanol gas. IDK where in the U.S. that there is more 100% gas compared to other regions of the U.S. I only know my area in which I live & buy fuel.
Also, some gasoline brands tout that they use the same detergent amount in all octanes of gas and others do not(the higher the octane, the more detergent).
I personally have not had any engine or fuel system failures by using just regular 87 octane w/ 10% ethanol. NOT in my vehicles, in which I have driven for decades & many 100K, 200K & 300K miles. NOR have I had any issues with my Outdoor Power Equipment(OPE).
Maybe my vehicles &/or OPE would/might run noticeably better with 100% gasoline but, I've never felt that they run poorly. Infact, everything that I own runs quite well, even perfect. They all start quickly, idle smoothly and rev freely on 10% ethanol 87 octane gas. And for the most part, meet the expected MPG!
However, there is a fuel economy benefit for 100% gasoline but, what is the delta on the paying higher prices for 100% gas as compared to just regular 87-93 octane. To me, it's all bottom line.
I have or had vehicles for 16, 18 & over 30 years and the same with lawnmower/snowblower, weedwacker/leafblower all without any fuel issues using just regular 87 octane fuel and over the past 25-30 years(that I am aware of), using 10% ethanol.
In most areas that I am aware of, 100% gas is only the highest octane gas at a filling station. All other lower octane gasoline is 10% ethanol gas. IDK where in the U.S. that there is more 100% gas compared to other regions of the U.S. I only know my area in which I live & buy fuel.
Also, some gasoline brands tout that they use the same detergent amount in all octanes of gas and others do not(the higher the octane, the more detergent).
I personally have not had any engine or fuel system failures by using just regular 87 octane w/ 10% ethanol. NOT in my vehicles, in which I have driven for decades & many 100K, 200K & 300K miles. NOR have I had any issues with my Outdoor Power Equipment(OPE).
Maybe my vehicles &/or OPE would/might run noticeably better with 100% gasoline but, I've never felt that they run poorly. Infact, everything that I own runs quite well, even perfect. They all start quickly, idle smoothly and rev freely on 10% ethanol 87 octane gas. And for the most part, meet the expected MPG!
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I'm not aware that premium octane fuel is inherently E-free. I live near a large lake that sees a lot of boating traffic and several stations in town sell ethanol free 89. I've also seen E-free 90 and 91. In my case, my 1961 Briggs-powered garden tractor gives me fits with ethanol fuel - even if I'm using it on a daily basis - but if it has E0 in it I can leave it sit for 6 months with no problems.
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All the premium around here is ethanol blended unless otherwise noted. CountryMark however does offer an ethanol-free premium 91 octane.
Originally Posted By: Alex_V
I'm not aware that premium octane fuel is inherently E-free. I live near a large lake that sees a lot of boating traffic and several stations in town sell ethanol free 89. I've also seen E-free 90 and 91. In my case, my 1961 Briggs-powered garden tractor gives me fits with ethanol fuel - even if I'm using it on a daily basis - but if it has E0 in it I can leave it sit for 6 months with no problems.
Yes, I too know folks(although it's rare these days) that still have 1960s-70s OPE and outboard boat motors/power watercraft(PWC) that don't like the E-10 fuel. However, I believe that everything you can buy today is designed for E-10 gas. These OPE/PWC may in fact run better on non E fuel but, I don't know that without trying the difference for myself.
I'm not aware that premium octane fuel is inherently E-free. I live near a large lake that sees a lot of boating traffic and several stations in town sell ethanol free 89. I've also seen E-free 90 and 91. In my case, my 1961 Briggs-powered garden tractor gives me fits with ethanol fuel - even if I'm using it on a daily basis - but if it has E0 in it I can leave it sit for 6 months with no problems.
Yes, I too know folks(although it's rare these days) that still have 1960s-70s OPE and outboard boat motors/power watercraft(PWC) that don't like the E-10 fuel. However, I believe that everything you can buy today is designed for E-10 gas. These OPE/PWC may in fact run better on non E fuel but, I don't know that without trying the difference for myself.
Can only get e10 here. Even at the lake.
Originally Posted By: Char Baby
Yes, I too know folks(although it's rare these days) that still have 1960s-70s OPE and outboard boat motors/power watercraft(PWC) that don't like the E-10 fuel. However, I believe that everything you can buy today is designed for E-10 gas. These OPE/PWC may in fact run better on non E fuel but, I don't know that without trying the difference for myself.
Yes, a lot of OPE I remember seeing of recent (2010>) manufacture has labels stating "E15 max" or similar. Strangely enough, my '67 Suburban is the only one of my vehicles that runs noticeably different on the E-free 89 than E10 of the same octane. And it's not the original engine - a stock '78 350 with its original smog heads (aka, designed after the change to unleaded fuel) but with all the 67's emission-free manifolds, carburetor, and ignition.
Yes, I too know folks(although it's rare these days) that still have 1960s-70s OPE and outboard boat motors/power watercraft(PWC) that don't like the E-10 fuel. However, I believe that everything you can buy today is designed for E-10 gas. These OPE/PWC may in fact run better on non E fuel but, I don't know that without trying the difference for myself.
Yes, a lot of OPE I remember seeing of recent (2010>) manufacture has labels stating "E15 max" or similar. Strangely enough, my '67 Suburban is the only one of my vehicles that runs noticeably different on the E-free 89 than E10 of the same octane. And it's not the original engine - a stock '78 350 with its original smog heads (aka, designed after the change to unleaded fuel) but with all the 67's emission-free manifolds, carburetor, and ignition.
Very hard, if not impossible, to find E0 gas around here.
Plenty of 93 octane with 10% ethanol, though.
Plenty of 93 octane with 10% ethanol, though.
E10 bleep gummed up my weed whacker and my Briggs powered genset, even though I am very careful about draining and adding Stabil. It caused a minor problem with my Honda mower, but Berrymans fixed that.
Originally Posted By: Speak2Mountain
We have access to 93 octane? I realize the bigger deal is detergent/additive pkg, but does octane and by extension 100% gasoline (no eth gas) have any bearing on Carbon buildup
No.
We have access to 93 octane? I realize the bigger deal is detergent/additive pkg, but does octane and by extension 100% gasoline (no eth gas) have any bearing on Carbon buildup
No.
Originally Posted By: Char Baby
Yes, I too know folks(although it's rare these days) that still have 1960s-70s OPE and outboard boat motors/power watercraft (PWC) that don't like the E-10 fuel. However, I believe that everything you can buy today is designed for E-10 gas. These OPE/PWC may in fact run better on non E fuel but, I don't know that without trying the difference for myself.
I'm one of those folks who has a slew of chain saws from the 1960's forward, older yard equipment, 1970's vehicles and outboard motors. They are not supposed to like E-10... But, guess what, I'm also cheap, so they get run on regular pump gas - always. And they all still run
The fuel lines in the small 2-strokes go away, but they are easy enough to change. Otherwise, they run fine.
Carbon build-up is all about mixture control. A well tuned engine hitting the right air/fuel ratios for the conditions will not build up much carbon. 2-stroke or 4-stroke. Get any of them slightly rich and you will build carbon ...
Yes, I too know folks(although it's rare these days) that still have 1960s-70s OPE and outboard boat motors/power watercraft (PWC) that don't like the E-10 fuel. However, I believe that everything you can buy today is designed for E-10 gas. These OPE/PWC may in fact run better on non E fuel but, I don't know that without trying the difference for myself.
I'm one of those folks who has a slew of chain saws from the 1960's forward, older yard equipment, 1970's vehicles and outboard motors. They are not supposed to like E-10... But, guess what, I'm also cheap, so they get run on regular pump gas - always. And they all still run
The fuel lines in the small 2-strokes go away, but they are easy enough to change. Otherwise, they run fine.
Carbon build-up is all about mixture control. A well tuned engine hitting the right air/fuel ratios for the conditions will not build up much carbon. 2-stroke or 4-stroke. Get any of them slightly rich and you will build carbon ...
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Is this question regarding GDI engines or just whatever ?
Yes, just wanting to know if E-Zero 93 octane gas would have a positive effect or no effect on my GDI engine.
Originally Posted By: Speak2Mountain
We have access to 93 octane? I realize the bigger deal is detergent/additive pkg, but does octane and by extension 100% gasoline (no eth gas) have any bearing on Carbon buildup
Using the correct octane rating will minimize any build up; but--
From experience, it can.
I once bought a vehicle in which the owner had used 93 octane instead of 87 - he said it was better since the number was higher. It pinged at idle and would knock under load with any octane lower than 93. Took a look in the spark plug hole and there was a noticeable amount of grayish buildup. I finally got it back to not pinging with 87 after a few months of blending gasoline grades to gradually reduce octane. This was an 80s vehicle so YMMV.
We have access to 93 octane? I realize the bigger deal is detergent/additive pkg, but does octane and by extension 100% gasoline (no eth gas) have any bearing on Carbon buildup
Using the correct octane rating will minimize any build up; but--
From experience, it can.
I once bought a vehicle in which the owner had used 93 octane instead of 87 - he said it was better since the number was higher. It pinged at idle and would knock under load with any octane lower than 93. Took a look in the spark plug hole and there was a noticeable amount of grayish buildup. I finally got it back to not pinging with 87 after a few months of blending gasoline grades to gradually reduce octane. This was an 80s vehicle so YMMV.
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My eB engine adjusts to octane but a number of owners suggest higher octane so we select the middle grade. It runs a bit stronger with that but never checked mileage since that was not an objective ...
Originally Posted By: BrocLuno
Originally Posted By: Char Baby
Yes, I too know folks(although it's rare these days) that still have 1960s-70s OPE and outboard boat motors/power watercraft (PWC) that don't like the E-10 fuel. However, I believe that everything you can buy today is designed for E-10 gas. These OPE/PWC may in fact run better on non E fuel but, I don't know that without trying the difference for myself.
I'm one of those folks who has a slew of chain saws from the 1960's forward, older yard equipment, 1970's vehicles and outboard motors. They are not supposed to like E-10... But, guess what, I'm also cheap, so they get run on regular pump gas - always. And they all still run
The fuel lines in the small 2-strokes go away, but they are easy enough to change. Otherwise, they run fine.
Carbon build-up is all about mixture control. A well tuned engine hitting the right air/fuel ratios for the conditions will not build up much carbon. 2-stroke or 4-stroke. Get any of them slightly rich and you will build carbon ...
The '80 Firebird FORMULA in my sig(all original) loves the E-10.
Originally Posted By: Char Baby
Yes, I too know folks(although it's rare these days) that still have 1960s-70s OPE and outboard boat motors/power watercraft (PWC) that don't like the E-10 fuel. However, I believe that everything you can buy today is designed for E-10 gas. These OPE/PWC may in fact run better on non E fuel but, I don't know that without trying the difference for myself.
I'm one of those folks who has a slew of chain saws from the 1960's forward, older yard equipment, 1970's vehicles and outboard motors. They are not supposed to like E-10... But, guess what, I'm also cheap, so they get run on regular pump gas - always. And they all still run
The fuel lines in the small 2-strokes go away, but they are easy enough to change. Otherwise, they run fine.
Carbon build-up is all about mixture control. A well tuned engine hitting the right air/fuel ratios for the conditions will not build up much carbon. 2-stroke or 4-stroke. Get any of them slightly rich and you will build carbon ...
The '80 Firebird FORMULA in my sig(all original) loves the E-10.
Originally Posted By: Kuato
Originally Posted By: Speak2Mountain
We have access to 93 octane? I realize the bigger deal is detergent/additive pkg, but does octane and by extension 100% gasoline (no eth gas) have any bearing on Carbon buildup
Using the correct octane rating will minimize any build up; but--
From experience, it can.
I once bought a vehicle in which the owner had used 93 octane instead of 87 - he said it was better since the number was higher. It pinged at idle and would knock under load with any octane lower than 93. Took a look in the spark plug hole and there was a noticeable amount of grayish buildup. I finally got it back to not pinging with 87 after a few months of blending gasoline grades to gradually reduce octane. This was an 80s vehicle so YMMV.
The long banned MMT which was used more in higher octane gas could cause deposits.
Originally Posted By: Speak2Mountain
We have access to 93 octane? I realize the bigger deal is detergent/additive pkg, but does octane and by extension 100% gasoline (no eth gas) have any bearing on Carbon buildup
Using the correct octane rating will minimize any build up; but--
From experience, it can.
I once bought a vehicle in which the owner had used 93 octane instead of 87 - he said it was better since the number was higher. It pinged at idle and would knock under load with any octane lower than 93. Took a look in the spark plug hole and there was a noticeable amount of grayish buildup. I finally got it back to not pinging with 87 after a few months of blending gasoline grades to gradually reduce octane. This was an 80s vehicle so YMMV.
The long banned MMT which was used more in higher octane gas could cause deposits.
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