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Running ethanol free gas??

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MNSTR said:
It's my understanding that higher octane fuel can be pressurized at higher rates, to therefore cause a more powerful explosion in the combustion chamber. This I why, typically, high performance engines require higher octane fuels. Higher your combustion ratio, the more octane you'll require to burn efficiently/properly. Putting lower octane fuel, in an engine that requires higher octane, will create a knocking in the engine. Caused by the fuel exploding prematurely. Putting high octane fuel in engines that don't require it, is essentially throwing money away. The engine will run fine though. All fuels have detergents in them to clean your fuel system, so that is a moot point. Just my 2 cents.....:cool:
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Higher octane fuels actually have less energy than lower octanes. Higher octane does not equal more power in an engine designed to run 87, its the opposite, it has less BTU than lower octanes. Its very minor, probably unnoticable, maybe even on a dyno.

Anywayysss, back to ethanol. Hey Pilot, you seem to know alot about this, I have a question.
How does ethanol content affect power? Ive heard some people say they use shell 91 no ethanol in engines designed to run 87 because they say they get more power when theres no ethanol. They say ethanol has a low energy. Thoughts?
 
catzo said:
Higher octane fuels actually have less energy than lower octanes. Higher octane does not equal more power in an engine designed to run 87, its the opposite, it has less BTU than lower octanes. Its very minor, probably unnoticable, maybe even on a dyno.

Anywayysss, back to ethanol. Hey Pilot, you seem to know alot about this, I have a question.
How does ethanol content affect power? Ive heard some people say they use shell 91 no ethanol in engines designed to run 87 because they say they get more power when theres no ethanol. They say ethanol has a low energy. Thoughts?
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It has nothing to do with btu's, or the energy ratings of various octane levels. All I was saying is, the higher the compression ratio of the engine, the more the air/fuel mixture is getting compressed before detonation, requiring higher octane to resist premature combustion. Higher amount's of fuel/air, and more compression, equals bigger boom, which in turn, equals more power!!
 
MNSTR said:
It has nothing to do with btu's, or the energy ratings of various octane levels. All I was saying is, the higher the compression ratio of the engine, the more the air/fuel mixture is getting compressed before detonation, requiring higher octane to resist premature combustion. Higher amount's of fuel/air, and more compression, equals bigger boom, which in turn, equals more power!!
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Ah, I see, so you were talking about the engines that use higher octane fuels, not the fuel itself? I misunderstood.

Btw theres slot more things at play than just compression ratio, but maybe you know that. Cam profiles, piston size, timing, its so complicated to me lol, I dont understand it all either haha. I thought it was all compression ratio until I realized my bike with a compression ratio of 12.1:1 uses 87 and my civic si with 11.0:1 uses 91 :/
 
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catzo said:
Ah, I see, so you were talking about the engines that use higher octane fuels, not the fuel itself? I misunderstood.

Btw theres slot more things at play than just compression ratio, but maybe you know that. Cam profiles, piston size, timing, its so complicated to me lol, I dont understand it all either haha. I thought it was all compression ratio until I realized my bike with a compression ratio of 12.1:1 uses 87 and my civic si with 11.0:1 uses 91 :/
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You are correct! Many variables to consider! My Ducati makes 112hp with 821cc's. My wife's care makes 140hp with 2000cc's!
It's a general way of approaching the subject if you don't fully understand what's going on inside! I know enough to know that I'm no expert!

Is the civic si turbocharged?
 
MNSTR said:
You are correct! Many variables to consider! My Ducati makes 112hp with 821cc's. My wife's care makes 140hp with 2000cc's!
It's a general way of approaching the subject if you don't fully understand what's going on inside! I know enough to know that I'm no expert!

Is the civic si turbocharged?
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Hell naw, naturally aspirated. But it feels like a turbo when dat vtec kicks in yo haha :D

Ive got a friend with an old saturn, s2 or something I think, 2.4L engine, 100hp. My bike has 98hp with an engine literally 1/4 the size, and any 600 SS nowadays will have more than 100.
 
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Static compression ratio is meaningless when comparing engines for octane requirements. There's a lot more to to it like cam timing and quench area etc. AFAIK 10% Ethanol blend will reduce the available BTU's of a given amount of gasoline by 5%, hence the mpg reduction.
 
DJM said:
Static compression ratio is meaningless when comparing engines for octane requirements. There's a lot more to to it like cam timing and quench area etc. AFAIK 10% Ethanol blend will reduce the available BTU's of a given amount of gasoline by 5%, hence the mpg reduction.
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This has been stated already, and dually noted. I was just generalizing for those that do not understand. Putting higher octane fuel into an engine that does not require it, is wasting money. Most people think higher octane ratings means cleaner, better mpg, etc.... This is simply not the case. Has to do with engine design/requirements.

Static compression is a factor, just not the only one. There are many variables at play.
I need alcohol......every forum is the same eh.......LOL
 
catzo said:
Higher octane fuels actually have less energy than lower octanes. Higher octane does not equal more power in an engine designed to run 87, its the opposite, it has less BTU than lower octanes. Its very minor, probably unnoticable, maybe even on a dyno.

Anywayysss, back to ethanol. Hey Pilot, you seem to know alot about this, I have a question.
How does ethanol content affect power? Ive heard some people say they use shell 91 no ethanol in engines designed to run 87 because they say they get more power when theres no ethanol. They say ethanol has a low energy. Thoughts?
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Look up combustion energy per mole of a substance to give you an idea of the amount of energy released. There are tables of this that you can find. The value is found using a calorimeter. As for ethanol and water and phase separation then there's some degree of truth to this because ethanol is a closer cousin to water than gas is (polar hydrophilic vs non polar hydrophobic) and thus can "attract" water from the atmosphere. However, I'm not sure how big this effect is since ethanol content is usually less than 5% in most fuel that I've seen.
 
jc100 said:
Look up combustion energy per mole of a substance to give you an idea of the amount of energy released. There are tables of this that you can find. The value is found using a calorimeter. As for ethanol and water and phase separation then there's some degree of truth to this because ethanol is a closer cousin to water than gas is (polar hydrophilic vs non polar hydrophobic) and thus can "attract" water from the atmosphere. However, I'm not sure how big this effect is since ethanol content is usually less than 5% in most fuel that I've seen.
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Interesting, thanks.
Where are you seeing 5%? Its all 10% now in ontario I thought. Some will say "guarenteed no more than 10%" but im pretty sure that means 10%. Only shell 89 is 5% and 91 is 0%.
 
Thought I'd seen that value at the pump. Not really been looking recently, maybe it's increased.
 
I try to only buy ethanol free simply because the gaskets / seals/ floats in a lot of the small engines and older bikes were just not a composition that works with ethanol . I have a couple jerry cans that I keep around for mowers, blowers, and chain saws. In my road bikes I'll buy it when I'm out of gas near a station that has it and I will never park one for the winter with ethanol in it.

some plastic bladder tanks (ducati) and particularily fiberglass tanks on motorcycles had real issue with exposure to ethanol.
 
crankcall said:
I try to only buy ethanol free simply because the gaskets / seals/ floats in a lot of the small engines and older bikes were just not a composition that works with ethanol . I have a couple jerry cans that I keep around for mowers, blowers, and chain saws. In my road bikes I'll buy it when I'm out of gas near a station that has it and I will never park one for the winter with ethanol in it.

some plastic bladder tanks (ducati) and particularily fiberglass tanks on motorcycles had real issue with exposure to ethanol.
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Curious about the real scientist science behind the ethanol debate, not the "I heard/read from a reputable source" science. I've occasionally forgotten to stabilize my ride over the winter and never had a startup problem. Three bikes, two carbureted. Almost always ran the swilliest grade of fuel, too. The B650's tank is plastic and doesn't seem to have deformed at all, while the sagging euro-tanks are undeniably real. I've seen the effects of a 92% ethanol solution on many plastics. Starts breaking them down within hours. Makes you wonder about all that cheap LCBO stuff in plastic containers.
 
I use Sta-bil stuff in my stored cars, mower, weedeater (etc) over the winter:

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but starting next winter will use Sta-bil 360 (if I can find it...) instead as it specifically mentions corrosion issues related to ethanol:

10625989_sbl_22284_pri_larg.jpg


Had an issue bringing my Mustang out of storage this spring that I believe may be related to phase separation: When I went to start it the 20A fuel pump fuse popped as did a 2nd one I tried. I thought it might have been that the Kenne Bell Boost-A-Pump in the back had gone off (though the car was running fine when I drove it to the storage place last fall). I removed the BAP and it bench tested fine so I re-installed it and the car started fine.

I now think that the pump may have been jammed due to a small amount of corrosion due to water in the bottom of the tank. The jostling of having it towed back to my place may have freed it to the point the torque of the pump motor could wipe away the remaining crud and now it's fine.

I suspect using E10 fuel in engines that are "in use" -- where the fuel is constantly being used, mixed around by motion, added-to etc -- is likely fine but storing such a car or bike or small-engine for months without some sort of stabilizer that specifically includes ethanol protections -- and not just fuel stabilization -- is just asking for trouble.
 
Flywheel said:
Curious about the real scientist science behind the ethanol debate, not the "I heard/read from a reputable source" science. I've occasionally forgotten to stabilize my ride over the winter and never had a startup problem. Three bikes, two carbureted. Almost always ran the swilliest grade of fuel, too. The B650's tank is plastic and doesn't seem to have deformed at all, while the sagging euro-tanks are undeniably real. I've seen the effects of a 92% ethanol solution on many plastics. Starts breaking them down within hours. Makes you wonder about all that cheap LCBO stuff in plastic containers.
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I dont know the science, but i replaced a fiberglass bike tank that ethanol ate , and have seen the blown engines in power boats from the fuel tanks , again fiberglass, melting out and the resin mixing with the fuel and creating a superheated cylinder. Its a pretty well documented problem in the marine industry.
 
crankcall said:
I dont know the science, but i replaced a fiberglass bike tank that ethanol ate , and have seen the blown engines in power boats from the fuel tanks , again fiberglass, melting out and the resin mixing with the fuel and creating a superheated cylinder. Its a pretty well documented problem in the marine industry.
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Also a well documented problem in the motorcycle industry for plastic composite tanks. Ducati, Triumph, Aprilia and more have all had issues with tanks swelling/deforming
 
Flywheel said:
Makes you wonder about all that cheap LCBO stuff in plastic containers.
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Those bottles sketch me out too. But the FDA says theyre fine.
To be fair to the FDA, its not the same plastic. For example, ducati gas tanks are made from Polyamide 6, which is the same thing the bristles on your toothbrush are made of. Its also used in alot of automotive applications. Under the hood bits. While the lcbo plastic bottles are made from high density polyethylene, which is a type of plastic known for resisting solvents (ie, alcohol).
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