What is "regular unleaded petrol" in Japan? RON92??

[Wishsing]

hi,my japanese car manual states use "regular unleaded petrol". can anyone here confirm on the octane grade of "regular unleaded petrol" used in Japan? seems like diff countries might hv diff definition for the same term.

[Nutty]

should be either 91 or 92.

[Wishsing]

Great!! i can pumped 92 now with a peace of mind.

dun worry, i wont hold u responsible if my engine knocks..

[Nutty]

Better confirm first la.

 

what is your ride?

[Panda]

I assume your ride is a 1.8 Wish.

 

Pump RON 95 dude.

[Qinglong]

doesn't the manual state the minimum?

[Glendon]

hi, how about a mit lancer?

[Ac67]

some manual states minimum as what the threadstarter posted.

 

like mine, the manual states 'regular unleaded gasoline'.

[Panda]

I have no idea what's "regular unleaded petrol" in Japan.

 

What I do know is, if its a Wish 1.8 1ZZ-FE engine with a compression of 10.0, then it should be on 95.

[Wishsing]

heh Thanks bro. u are spot-on. i am driving a New Face-Lift 2006 Wish 1.8

i have "downgraded" fr. 98 to 95 recently. was planning to go down to 92. i didnt know WISH is on 10:1 compression. so you reckon, the engine will "knock" with 92?

 

look forward to your advice.

[Genie47]

It will knock and then you actually don't feel it because when the ECU senses the knock, it retards the ignition.

 

Nothing will happen but your fuel economy and power will suffer.

[Wishsing]

i definitely lack the technical know-how but wat i understood is that if a lower Octane level petrol is used.. it will combust pre-maturely when it is compressed "too much" (depends on the compression ratio of the engine). higher octane-level petrol has higher tolernace- can be compressed more before it combust. will "retarding" the ignition help?

[Genie47]

Actually more complicated than that.

 

Retarding the ignition helps but to what avail? The engine won't be damaged but you will lose power and your fuel economy will suffer.

 

What you saved from pumping with RON92 is lost through the poorer fuel economy when compared with 95. Since this is a JDM engine, it can and will use up to RON100! So there you have it. If you use 98, you will gain the best fuel economy but are the gains worth it?

 

Take the middle ground and save some of your cash. 95 is a good compromise.

 

Try 95 for 5 tanks and then 98 for 5 tanks. Average them out. Calculate your economy by $/km. Economy is about saving money not just bigger km/L figures.

[Boyboy]

ok a noob qn.. i know u did say sth abt the grocery getters not needing good petrol, will there be a diff for me if i pump 95 for my 1.1 getz? over RON 92. will the engine be able to "make use" of the added octane to give better economy?

 

still running in and stupid oil cartels have their $3 off which makes it hard to pump full tank. a bit hard to calculate FC also on a per tank basis.

 

first pump was ron 95 shell. 2nd pump ron 92 mobil. but second tank seems a bit better probably cos the engine is being run in. or maybe it's just me

[Nutty]

Genie will ask you to go test it out yourself.

[Boyboy]

haha.. actually i would..

 

my manual says min RON 91. but i dunno if the engine is smart enuff to make use of higher grade. i'm interested in cost per km and not absolute FC. but if engine is retarded, higher grade wun improve FC, by right.

[Genie47]

One tank not enough. 1 month (5 tanks assuming you travel 500/week). Its true you don't need good petrol but at the same time you want petrol that can save money when it comes to the $/km result.

 

You can't just save here so that you waste it off by spending over there.

Edited October 19, 2006 by Genie47

[Genie47]

1.1L Getz? Confirm like mine. Retarded.