What type of gas to fill up with?
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From: Palm Beach Gardens, Florida, US
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What type of gas to fill up with?
Will filling up with mid-plus gas(87 octane) or relgular(86 octane) make a big difference in performance. Someone told me filling up with a high octane level like premium can mess some cars up, because the engine is not made for it.
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Rep Power: 0 I think this is how it works.........Its shouldn't make a difference in performance if your car was made to use 87 octane. Because with a higher octane, all that means is that the fuel will withstand a lot more compression before being ignited by the compression itself. So what I am trying to say is that fuel ignites by itself at a certain amount of compression. 87 octane will ignite with less compression then the 91. So with a higher octane and a low compression ratio the fuel will surely be ignited by the spark plugs. But if you use a 87 octane on a engine that is designed to use 91 octane (meaning engines with a higher compression ratio) then your fuel/air mixture may ignite pre-maturely causing knocking in your engine and that could mess things up.
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From: Oakland, California, US
Rep Power: 0 Well, our cars weren't made to take only 86, it says 86 or higher.
I think you should experiment with it yourself. Personally, 87 compared to 89 sucks... and 91 is no different than 89 so I use 89. THIS IS HOW I SEE IT because I know some people who don't mind filling up with 91 and of course I see no point to it. Some people don't notice a difference between the different octanes while some do. I think in the end, it's an unarguable personal preference with our cars - and of course common sense says you should never fill up with a gas under the recommended octane #.
I think you should experiment with it yourself. Personally, 87 compared to 89 sucks... and 91 is no different than 89 so I use 89. THIS IS HOW I SEE IT because I know some people who don't mind filling up with 91 and of course I see no point to it. Some people don't notice a difference between the different octanes while some do. I think in the end, it's an unarguable personal preference with our cars - and of course common sense says you should never fill up with a gas under the recommended octane #.
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Rep Power: 0 i always use the highest becuase i tend to floor my car off of evry start and i can tell the difference in sound once the engine hits 7-7.5 rpms. when my stepmomm puts in crapppy gas in i can tell becuase instead of car taking off instantly into the next gear it has a sortof pause in between switching gears. i dunno aout anybody else but i try to get as much speed as i can from my slow peice of metal, plastic and other stuff they call civic.
riley
riley
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From: dirty jerz
Rep Power: 0 while i don't know how the ECU in our cars works, i can tell you this...
with my '86 944 and alot of more modern cars the computer has a knock sensor that lets the computer inject more fuel into the cylinders when higher grades are used... on the dyno, the 944 gained 7 ft/lbs of torque and 11.5 hp using sonoco ultra 94 vs. mobile 89
with my '86 944 and alot of more modern cars the computer has a knock sensor that lets the computer inject more fuel into the cylinders when higher grades are used... on the dyno, the 944 gained 7 ft/lbs of torque and 11.5 hp using sonoco ultra 94 vs. mobile 89
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From: Connecticut, US
Rep Power: 0 Using higher octane gas will actually foul up your fuel system faster. Anything higher than 86 will do nothing for your car performance wise. If we had knock sensors, than it would be a different story...but we don't. The only reason Honda tuned our cars for 86 was to protect against pre-detonation since you'll be using 87 octane.
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[hr]Originally posted by: PESTLNC
Using higher octane gas will actually foul up your fuel system faster. Anything higher than 86 will do nothing for your car performance wise. If we had knock sensors, than it would be a different story...but we don't. The only reason Honda tuned our cars for 86 was to protect against pre-detonation since you'll be using 87 octane.[hr]
[hr]Originally posted by: PESTLNC
Using higher octane gas will actually foul up your fuel system faster. Anything higher than 86 will do nothing for your car performance wise. If we had knock sensors, than it would be a different story...but we don't. The only reason Honda tuned our cars for 86 was to protect against pre-detonation since you'll be using 87 octane.[hr]
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From: Connecticut, US
Rep Power: 0 Wow, I've said that over and over again here...you seem to be the first person that actually gets it. This site needs a FAQ including this as one of the topics, as it pops up every couple weeks.
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From: Tempe, Arizona, US
Rep Power: 0 I agree with everything you said except for "Using higher octane gas will actually foul up your fuel system faster. "
Why would that happen? The engine is tuned to use a lower octane gas, so I would think it wouldn't make a difference performance wise or fuel system wise.
Why would that happen? The engine is tuned to use a lower octane gas, so I would think it wouldn't make a difference performance wise or fuel system wise.
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From: Connecticut, US
Rep Power: 0 Using higher octane gas on a car tuned for something lower will increase the chance of getting an incomplete burn...resulting in fouled plugs, lower performance, and lower fuel efficiency.
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[hr]Originally posted by: PESTLNC
Using higher octane gas on a car tuned for something lower will increase the chance of getting an incomplete burn...resulting in fouled plugs, lower performance, and lower fuel efficiency.[hr]
[hr]Originally posted by: PESTLNC
Using higher octane gas on a car tuned for something lower will increase the chance of getting an incomplete burn...resulting in fouled plugs, lower performance, and lower fuel efficiency.[hr]
Either way I don't understand why it would make a difference in the type of octane you use then, because using a different octane does not change the chances of the spark igniting the all fuel, regardless of the type of fuel you use. I don't think a different octane is going to change the chance of the fuel getting ignited by a spark. I don't think that compression of the fuel matters when it has reached the spark phase the compression cycle.
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From: Connecticut, US
Rep Power: 0 That may be true on our engines...I don't know. Most of my knowledge is on much much larger displacement engines. But...even if we do get a complete burn think of it this way...
Our engines compress 87 octane gas to the optimal pressure before igniting it. Our engines will NOT compress 89, 91, 93, etc. octane to their optimal pressure before igniting it. Simply speaking, regular unleaded explodes best in our engines.
Our engines compress 87 octane gas to the optimal pressure before igniting it. Our engines will NOT compress 89, 91, 93, etc. octane to their optimal pressure before igniting it. Simply speaking, regular unleaded explodes best in our engines.
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[hr]Originally posted by: rijowysock
i always use the highest becuase i tend to floor my car off of evry start and i can tell the difference in sound once the engine hits 7-7.5 rpms. when my stepmomm puts in crapppy gas in i can tell becuase instead of car taking off instantly into the next gear it has a sortof pause in between switching gears. i dunno aout anybody else but i try to get as much speed as i can from my slow peice of metal, plastic and other stuff they call civic.
riley[hr]
[hr]Originally posted by: rijowysock
i always use the highest becuase i tend to floor my car off of evry start and i can tell the difference in sound once the engine hits 7-7.5 rpms. when my stepmomm puts in crapppy gas in i can tell becuase instead of car taking off instantly into the next gear it has a sortof pause in between switching gears. i dunno aout anybody else but i try to get as much speed as i can from my slow peice of metal, plastic and other stuff they call civic.
riley[hr]
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[QUOTE]Quote
[hr]Originally posted by: SoNiCcIvIc
Well, our cars weren't made to take only 86, it says 86 or higher.
So your saying I won't have any problems running 118 octane fuel?
[hr]Originally posted by: SoNiCcIvIc
Well, our cars weren't made to take only 86, it says 86 or higher.
So your saying I won't have any problems running 118 octane fuel?
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From: Oakland, California, US
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[hr]Originally posted by: 2k2civic
LoL, hell no! I'm saying what the Civic manual says. An octane that high defintely is not good on our engines. 
[hr]Originally posted by: 2k2civic
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[hr]Originally posted by: SoNiCcIvIc
Well, our cars weren't made to take only 86, it says 86 or higher.
So your saying I won't have any problems running 118 octane fuel?[hr]
[hr]Originally posted by: SoNiCcIvIc
Well, our cars weren't made to take only 86, it says 86 or higher.
So your saying I won't have any problems running 118 octane fuel?[hr]
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From: Juneau, Alaska
Rep Power: 0 For those of you who are knowledgable in this area...
Would one want to step up an octane upon installing multiple bolt-on items (i.e. intake, header, exhaust, high flow cat, etc.)?
Just wondering because when I run 94 octane(yep, at the Chevron stations) on my trips to Whistler, B.C. in Canada, the car runs very nicely. But since that's not available here in Washington I typically run either 87 or 89.
TJ
Would one want to step up an octane upon installing multiple bolt-on items (i.e. intake, header, exhaust, high flow cat, etc.)?
Just wondering because when I run 94 octane(yep, at the Chevron stations) on my trips to Whistler, B.C. in Canada, the car runs very nicely. But since that's not available here in Washington I typically run either 87 or 89.
TJ
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From: fullerton, California, US
Rep Power: 0 If the engine was tuned for the lower octane levels, why does the manual say 'and up'? It says that by using higher octane, you are just wasting money.
I use Mobile 91 just because it's what, $2 extra for a full tank every two weeks? Some people swear to 91. So for $4/month, why not? I didn't know it could be bad...
I drove from Southern California to Northern California. Did get about 42MPG using 91.
I use Mobile 91 just because it's what, $2 extra for a full tank every two weeks? Some people swear to 91. So for $4/month, why not? I didn't know it could be bad...
I drove from Southern California to Northern California. Did get about 42MPG using 91.
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[hr]I'm saying what the Civic manual says. An octane that high defintely is not good on our engines. [hr]
[hr]I'm saying what the Civic manual says. An octane that high defintely is not good on our engines. [hr]
since when do us civic owners follow the manual.... haha, we do anything to our cars
as for me, i used to use 87 octane, .... then i switched to 89 octane and i realized i got about 80km n(dont know how much that is in miles...50miles?) more out of the gas tank... and i got a lil more jump off the start... it doesnt lag as much.
i have a standard
