Civics have octane requirement of 86???

[fleabag]

I don't understand, why does the owner's manual of the '92-'05 Honda civic say that the octane requirement is 86? I understand one can use 85 at higher altitudes if their car requires 87 but from what I'm seeing, the Honda Civic from '92-'05 (I don't know about the others) specifically says Octane of 86 or higher.. Why doesn't it have an Octane Requirement of 87 like most other vehicles? Had they set a requirement of 87, wouldn't that allowed them to get a wee bit more performance out of these things?

What is the minimum/requirement octane for an '06- civic? For those who are wondering, I'm not talking about Si but the regular run of the mill civics..

 

[Zenmervolt]

Why doesn't it have an Octane Requirement of 87 like most other vehicles?

Not all countries have the same available grades of gasoline as the US. Also, most countries outside of North America use RON rather than the US (RON+MON)/2 value (also known as AKI) for a gasoline's octane rating. Because of variances in conversion between these two numbers, it is possible that one company may list 86 as the US/Canada equivalent to what is listed as 91 RON elsewhere, while another company may list that same 91 RON as equivalent to 87 in the US/Canada.

This is the most likely reason. The engines are probably world engines and are designed to run on 91 RON fuel, which Honda's conversion tables equated to 86 AKI.

Had they set a requirement of 87, wouldn't that allowed them to get a wee bit more performance out of these things?

Technically yes, but the real-world difference is simply not enough to ever be noticeable by a driver and, given what I said above, would require that Honda create a special tune just for US/Canada rather than being able to realize the cost savings from having a single engine used in various countries/continents.

What is the minimum/requirement octane for an '06- civic? For those who are wondering, I'm not talking about Si but the regular run of the mill civics..

IIRC the owner's manual lists 87 as the minimum with 91 "recommended". This phraseology typically means that the engine can run perfectly fine forever on 87 octane fuel, but the engine management software is capable of advancing the timing enough to make use of 91 octane fuel if you choose to put it in.

ZV

 

[Bignate603]

Good post ZV.

Honestly, even if they did design the engine for 86 octane rather than 87 the differences will be so small that you'd never notice. You'll get significantly more of an increase in performance by normal maintenance like keeping your air filter clean.

 

[fleabag]

This is the most likely reason. The engines are probably world engines and are designed to run on 91 RON fuel, which Honda's conversion tables equated to 86 AKI.

ZV

What do you mean by "Honda's conversion tables equated to 86AKI? I mean I understand what you've posted except for this part.. Wouldn't the equation be pretty linear if it's MON+RON/2 ? Here is the better question, what kind of fuel are they basing this off of? I looked at the wiki for octane rating but it didn't give me enough to be able to calculate and get 86 "us" octane.

 

[Eli]

What do you mean by "Honda's conversion tables equated to 86AKI? I mean I understand what you've posted except for this part.. Wouldn't the equation be pretty linear if it's MON+RON/2 ? Here is the better question, what kind of fuel are they basing this off of? I looked at the wiki for octane rating but it didn't give me enough to be able to calculate and get 86 "us" octane.

In the US, our Octane is MON+RON/2. In other countries, it is RON.

He's saying that in Honda's conversion table it is likely that MON+RON/2=86=RON-91.

 

[zoiks]

I was in the UK recently and the super unleaded was 98oct.

 

[fleabag]

In the US, our Octane is MON+RON/2. In other countries, it is RON.

He's saying that in Honda's conversion table it is likely that MON+RON/2=86=RON-91.

Oh so the standard in europe is a Research Octane Number of 91? That would give a motor octane of only 81! Why use a combination of these ratings when they should just use the Motor octane number? (Motor octane number is achieved through more stringent testing)

 

[KentState]

You only need to use 87 if you inflate the tires to the max sidewall pressure.

 

[TehMac]

Its a confusion in terms of measurement of the grade of Octane. It's why Jeremy said, "And that's if the [CCX Koenigsegg] is running on the limp wristed fairy liquid the Americans call petrol. If you run this on the more explosive jungle juice we have here in Europe, you'll be getting 850 bhp. (stated bhp is 806 bhp on the "American stuff."

My theory is that:
a) JC as usual doesn't know what he's talking about
b) He mistook the AKI measurements here to be same as the RON measurements in Europe

c) Idk, ZV what do you say?



link here

 

[Bignate603]

You only need to use 87 if you inflate the tires to the max sidewall pressure.

Only if you want to get 50 mpg while going up a hill without downshifting so its possible for you to start going to the gym.

 

[Demon-Xanth]

From Wikipedia:
RON MON AKI
"regular" gasoline in Canada and the US 91–92 82–83 87
"EuroSuper" or "EuroPremium" 95 85–86 90–91
"premium" gasoline in the US 97-98 88–89 93
"SuperPlus" in Germany, Great Britain and Slovenia 99 89–90 93–94

...that said, all I see around here for premium is 91, never 93 anymore. (stupid CARB...)

You can find this stuff, but cheap it ain't.
http://www.sunocoinc.com/Site/Consumer/RaceFuels/UnleadedFuels/Sunoco260GT.htm

 

[EightySix Four]

From Wikipedia:
RON MON AKI
"regular" gasoline in Canada and the US 91–92 82–83 87
"EuroSuper" or "EuroPremium" 95 85–86 90–91
"premium" gasoline in the US 97-98 88–89 93
"SuperPlus" in Germany, Great Britain and Slovenia 99 89–90 93–94

...that said, all I see around here for premium is 91, never 93 anymore. (stupid CARB...)

You can find this stuff, but cheap it ain't.
http://www.sunocoinc.com/Site/Consumer/RaceFuels/UnleadedFuels/Sunoco260GT.htm

Mmmm... 93 octane is still around Dallas, but no sunoco 100

 

[Excelsior]

I can still get 93 octane here in Charlotte, NC.

 

[OILFIELDTRASH]

My wife's civic '08 says to run 87 octane.

 

[Zenmervolt]

Oh so the standard in europe is a Research Octane Number of 91? That would give a motor octane of only 81! Why use a combination of these ratings when they should just use the Motor octane number? (Motor octane number is achieved through more stringent testing)

Because what they list doesn't matter. It's still the same gasoline. Whether they call it 91 RON, 81 MON, or 86 AKI, it's still the same goddamn thing. There is absolutely no chemical difference between the gasoline.

ZV

 

[Zenmervolt]

Its a confusion in terms of measurement of the grade of Octane. It's why Jeremy said, "And that's if the [CCX Koenigsegg] is running on the limp wristed fairy liquid the Americans call petrol. If you run this on the more explosive jungle juice we have here in Europe, you'll be getting 850 bhp. (stated bhp is 806 bhp on the "American stuff."

My theory is that:
a) JC as usual doesn't know what he's talking about
b) He mistook the AKI measurements here to be same as the RON measurements in Europe

c) Idk, ZV what do you say?

link here

US gasoline tops out at 92 AKI for widely-available gasoline (CA tops out at 91 and a few states have 93, but 92 is the most widely-available "Premium" gasoline). Most manufacturers max out their US tunes for only 91 AKI since that's the most that can be guaranteed and since CA accounts for a disproportionate amount of the supercar market in the US.

99 RON (equivalent to 94 AKI) is widely available in the UK and in Germany however, which allows manufacturers to tune European editions for 94 AKI.

That gives the European versions of these cars an advantage.

ZV

 

[jlee]

I can still get 93 octane here in Charlotte, NC.

Same here in NH. Farther north (Littleton) I think they had 94, but I can only get 93 here.

 

[lurk3r]

93 all over the place here, 94 in Sunoco, and 110 in one special little Citgo on Woodward.

 

[SSSnail]

Contrary to popular beliefs, higher octane does not necessarily equate to higher performance. It depends on the compression of the engine, and ignition system capability.

Higher octane fuel has a slower burn rate, so it requires higher compression to achieve complete combustion. In a low compression vehicle, the higher octane fuel won't be able to burn completely, therefore will leave a lot of unburned or partially burned fuel, which is neither good for your car or environment. 86 or 87, it doesn't make a damn difference; going from 86 to 91, yes it makes a difference.

So, don't think that you'll be doing your car any good when you put higher octane fuel in it when the recommendation is something else.

 

[LTC8K6]

Sunoco is quickly phasing out 94Ultra, iirc. It's becoming 93Ultra.

 

[TridenT]

I think it said 86 in my 2000 honda civic ex(I think this is the D16Y8 engine with 127hp) coupe operating manual...

Not like I really care though... I just get fucking regular gas when I fill it up. :/

 

[coxmaster]

I think it said 86 in my 2000 honda civic ex(I think this is the D16Y8 engine with 127hp) coupe operating manual...

Not like I really care though... I just get fucking regular gas when I fill it up. :/

Uh.. that is regular gas.

 

[TridenT]

Uh.. that is regular gas.

Thus why I get regular gas...

 

[jlee]

Sunoco is quickly phasing out 94Ultra, iirc. It's becoming 93Ultra.

Figures. Just as long as they don't go down to 91..that would suck.