Super unleaded vs hioctane

[waitnbl33d]

@XaXooboy: Super is more then enough for all the regular cars here in pakistan such as civic, cultus, corolla, accord cl9. Even cygnus and prado can be run very easily on Super.

The reason being that super has a Ron level of 89 which is more then enough for these cars.

Hi-octane has a Ron level of 96. These are quoted from Shell, when I asked them.

Hi-octane would become necessary if you are running high compression pistons or forced-induction like a turbo or NOS. These vehicles require a higher level of octane otherwise they would knock a lot.

The petrol pump guy put in Super mistakenly in my Evo once and i was getting knocks upto 80 on my powerfc. I had to top it up with Hi-octane to reduce the knock.

[levin]

hioctane all theway if you can afford it. better combustion ontime and less fuel needed to rev up engine to the torque needed to drive, plus easy driving. no pings and knocks. civic takes 98 ron, read the fuel cap cover there is the sticker there posted by Honda for ppl who like to read than just listening to others.

[waitnbl33d]

@levin: i don't own a civic or i would have read the fuel cap.

But i did read the following off the internet:

a link to the 2008 Honda Civic owners manual for American models:

https://techinfo.honda.com/rjanisis/pubs/om/ACV080/ACV0808OM.pdf

Check page 180 which states that Civic's minimum requirement is a pump octane level of 87 (PON is for America) which converts to 91 RON (for europe/asia)

98 RON would be good for turbocharged vehicles or high compression vehicles.

Ofcourse if you put hi-octane, it would be better combustion, but there's no need to spend more when Super does the job.

Attached Pic of page 180

[HumanGenius]

@levin
I believe 98 RON is the hi-octane fuel.

Whereas on the fuel cap of my Vti 03 it says "Premium/Super Unleaded" which is the standard gasoline (@57/L)

@all
I read on PW that it is dangerous to run a car purely on HOBC. It must be mixed with petrol otherwise just HOBC will induce some mechanical problems...true?

[RetardedBuddy]

Yeah i've heard the same, can someone explain

[waitnbl33d]

cars are tuned for a specific RON level.

ordinarily super unleaded is what the cars are tuned for and thus they perform satisfactorily on it.

if you put HOBC in a car tuned for super then you are raising the RON level but not increasing the AIR so thus improper combustion will take place and unburnt fuel wil exit your engine.

Every car has to maintain a air to fuel ratio to perform satisfactorily.

[levin]

it says 95ron/premimium , superunleaded on civic. not 98ron- my mistake but yr superunleaded is 95ron? if yes then its ok,

[riz_]

My knowledge is limited to USDM models only. Most vehicles sold here since the late 90’s have the capability to sense the octane level and adjust the air/fuel mixture appropriately. Most Ford and GM non-hybrid vehicles can also detect E85 fuel and adjust ignition accordingly.

Super Unleaded is a confusing term. Here in the US, it could mean 91 or 93 octane. There is NO official requirement to formulate Super Unleaded with specific octane level. It is just a term used to signify fuel with higher than standard octane level which is 87. At the moment Hyundai is the only automaker that states HP numbers for both 87 and 91 fuel. Since most vehicles sold here are designed to run on 87 fuel, no one else really cares to officially quote performance numbers for 91 or 93.

[levin]

98 civic used in Russia and neighbouring countries like Pakistan

[farazgenius]

take 63 % high octane and 37% super/premium... mix thm togather .... and get 95 ron/roz for ur civic... my 99-00 civic gives me the boost...(Y)(Y)(Y)

[levin]

so what is the ron level of local hioctane?

[waitnbl33d]

i enquired from Shell a while back and they told me its 96 Ron for Hi-octane.

[levin]

they dont even sell 96ron in USA on public pump, how can they sell 96ron in PK?

are we more advanced than USA in maintaining cars?

[Bilaltq]

Reply By : riz_ on 1/5/2009 9:45:40 PM
My knowledge is limited to USDM models only. Most vehicles sold here since the late 90’s have the capability to sense the octane level and adjust the air/fuel mixture appropriately. Most Ford and GM non-hybrid vehicles can also detect E85 fuel and adjust ignition accordingly.

Super Unleaded is a confusing term. Here in the US, it could mean 91 or 93 octane. There is NO official requirement to formulate Super Unleaded with specific octane level. It is just a term used to signify fuel with higher than standard octane level which is 87. At the moment Hyundai is the only automaker that states HP numbers for both 87 and 91 fuel. Since most vehicles sold here are designed to run on 87 fuel, no one else really cares to officially quote performance numbers for 91 or 93.

Aren't most engine combustion ratios set for normal 87 octane?

[Bilaltq]

Reply By : levin on 1/6/2009 10:44:59 AM
they dont even sell 96ron in USA on public pump, how can they sell 96ron in PK?

are we more advanced than USA in maintaining cars?

It's possible. Shell V-Power is 97 octane.

EDIT:
97RON.

[waitnbl33d]

@levin: yes we have better fuel then them,

it comes as a surprise really but our Hi-octane is far better then most developed countries.

i guess we buy petrol from better sources.

having said that the people of evom and supra forums are amazed when we tell them that we are running 2 bar supras and 2.2 bar evos on pump gas.....they would never try it there, they would run racegas for anything above 1.5 bar.

[levin]

on average 92 to 94ron was sold in usa when i was there and still is as indicated by PW members living in usa now

https://www.pakwheels.com/forumreply_az_TopicID!93828~ForumID!31~pw.html

other than that bilaltq has found 97 ron somewhere in florida.

unless proved PK has higher ron level it is very difficult for me to beleive Pk would sell higher ron level than 91 on maxside. I understand it is very expensive to purify fuel to sell at higher rons as far as cost is concerned.

I dont want to argue against your sources at SHell Pakistan but i also believe many pakistani have exagerated figures to upsell their products and often i found variations on actual and what is told by seller in various products.

[levin]

both 4g63 and 2jzgte run on force air. take a high compression naturally aspirated engine and chk fuel rons comparision, na engines rely directly upon fuel and has no additionalforce.

[Bilaltq]

Okay let's take the 2AZ-FE for example.

Compression ratio is 9.8:1
Requires 91RON Unleaded.

Now is 91 RON different that 91 Octane? What about MON? What's Motor Octane Number?

[waitnbl33d]

@levin: yes true you can't rely on people here,

As for NA cars we are running an all motor civic b18c which has a compression of 13.1:1 ...and its running well on hi-octane, no knocks what so ever.

Anyhow as long as our everyday cars are running fine on super and our sports/luxury cars are running on hi-octane we have nothing to worry about