Research Octane Number
You might have seen numbers like RON97 and RON92 at your neighbourhood petrol station. Fuel with a RON97 rating is more expensive, RM1.92 per liter at time of writing with the lower RON92 rating going for RM1.88.
Have you ever wondered what they mean? Why is RON97 more expensive than RON92, and can you use RON92 to save on fuel costs?
Let’s have a discussion. What petrol do you use regularly, and why do you like your choice of petrol? Or are they all the same to you?
RON97, RON92, who is this RON person?
You might have seen numbers like RON97 and RON92 at your neighbourhood petrol station. Fuel with a RON97 rating is more expensive, RM1.92 per liter at time of writing with the lower RON92 rating going for RM1.88. Have you ever wondered what they mean? Why is RON97 more expensive than RON92, and can you use RON92 to save on fuel costs?
RON stands for Research Octane Number, a rating used to measure a fuels knocking resistance in spark-ignition internal combustion engines. Before we attempt to understand this mumbo jumbo, we have to know what knocking is. Knocking is what happens when parts or all of the air-fuel mixture prematurely ignites before the flame from the spark plug can reach it. This can be caused by ignition timing that is too early or engine overheating, where the heat from the cylinder itself causes the mixture to combust before the spark plug can burn the mixture. This causes a decrease in performance and might also harm the engine.
It is a misunderstanding to think that RON97 fuels produce more power than RON92 fuels, even more so with the fact that in reality a higher RON number means the fuel burns less easily! RON refers to the ability of the fuel to resist knocking and nothing else.
By pumping the RON97 into a car which engine only requires the RON92, all youre going to get is an emptier wallet – hardly counts for performance gains via weight reduction! 
Engines are designed to have a minimum RON rating for its fuel. Do check your service manual for the minimum RON rating that it requires. For engines that require a minimum of RON92, you might as well pump RON92 fuel and save abit of money since RON92 is cheaper by 4 cents per liter. Another common minimum RON rating is RON95, but since we do not have RON95 fuel in our market, we have to use RON97 fuel for the engine. These engines normally have higher compression ratios, like the one found in the Satria GTI so it needs higher knock resistance to withstand higher compression.
If you find that your engine can use RON92 petrol and decide to save abit of money, do check out if a petrol stations RON92 petrol is leaded or unleaded. All RON97 petrol is unleaded, but some RON92 petrol might be leaded although this is very very rare. Buy me a teh tarik with the money you save, thanks! 
July 25, 2006 @ 11:41 am
i like petronas.
July 25, 2006 @ 11:43 am
i love petronas
July 25, 2006 @ 12:02 pm
for rx8, i was told by a cycle&carriage salesman that it requires RON100 fuel.
its available in japan but not here. the highest we have is v-power with RON98. anyhow thats why rx8 here will be sold after 3years he said as knocking from the engine will eventually crack the apex seal for the rotor engine.
July 25, 2006 @ 12:07 pm
Isn’t V-Power RON97 with additives?
What is the octane rating of Shell V-Power?
The Research Octane Number (RON) is 97.0 minimum and all cars can use this petrol.
From: http://tinyurl.com/jcc82
V-Power is called Optimax in other countries and those are RON98, but it seems that our local V-Power is RON97.
Anyway I did some researching, the RX8 seem to require a minimum of RON93.
July 25, 2006 @ 12:13 pm
petronas seldom ve ron92… okie, looks like i am gonna pump more ron92 after this, lets pollute the earth!!.. mobil esso, bp, caltex usually ve ron92…. so what is good with ron97? no lead?..cleaner engines?
July 25, 2006 @ 12:14 pm
these days ron92 is unleaded also, like the projet ron92. some people have said that mobil ron92 is leaded though, not confirmed!
ron97 has higher knock resistance, that’s all.
July 25, 2006 @ 12:19 pm
Haiya.. forgot la.. can somebody help me, ex850 can use ron92 or not?
July 25, 2006 @ 12:30 pm
shell v-power is RON 97. besides of talking about the RON number only, additives inside the petrol must also be taken into considerations. that is why some of the petrols are marketed as enhancing fuel economy, while others are marketed as power enhancing. the new primax 3 is touted as fuel enhancing fuel by cleaning your engine from all the carbon deposits, hence restoring the efficiency of your engine. v-power touted as power enhancing fuel, give more power to you, but may contain less of cleaning properties.
for shell, there are v-power and there are optimax. 2 different blend of fuel.
for requirements of imported cars usually from japan, it depends on the models. that is why there is a grey importer and there is official importer. for grey importer, you do not have to homologate the car to the situations / conditions in malaysia, whereas for an official importer, you have to homologate the cars to this country conditions. point of note, impreza sold in japan requires 100 octane fuel which is readily available there, but even the impreza sti imported to USA cannot tolerate their piss water fuel, therefore usa’s sti got the 2.5L engine, the 2.0l engine inside the normal impreza have to be detune to tolerate the level of fuel over there.
however you can still buy the rx8 which require the 100octane fuel and fill it up with our 97octane fuel, but all the engine parameter like the ignition timing will be pull, your engine would not be as smooth as it should be, because with all the sensors, the ECU will reduce the engine power output to tolerate the fuel. your engine would not blow, but you would nbot feel the full power either.
July 25, 2006 @ 1:08 pm
there was a great report on WhatCar Magazine last month….comparing different fules on the same car.i tink it was M5 and Celica 1.8…different fuel brand and octane numbers did give different HP and torque numbers….using dyno testing….on some fules…the car reached its peak torque at lower rpm than others petrols…while othrs had slightly more hp at the end of the power band…some ‘felt’ smoother engine while othr petrols had a rougher sound to it….i tink thy all had almost same interms of fuel savings…it was very interesting..i personally use primax3 …i mite not be right bt from wat i feel…its feels smoother than othrs….and my Campro wil have no pinging at all….Campro’s from wat i know are very petrol sensitive….i tink wateva u use…fuel saving is all psychological….the best way is to have a lighter rite foot on ur pedal!
July 25, 2006 @ 1:22 pm
Still don understand, btw at miri here, at shell i can only get super, only some old station sell regular.
as for petronas, all now sell PRIMAX 3 (that’s the hot topic ppl at other forum talk)
i have pump my 1st tank of primax 3 last night, right after i received the voucher that i won : ) - RM10
i have read the monster blog, but how do we actually know what RON our car require??
but i think now a day car will use RON 97. coz normal car compression for 10:1
still need some more expert advice : )
July 25, 2006 @ 1:42 pm
Most station in the city and suburban area (apart from Projet) usually RON97-only. It’s hard to find (at least for me) Petronas with RON92 while Shell have went RON97-only since a while ago.
July 25, 2006 @ 1:47 pm
RON 95 is for Proton Iswara.Meaning can’t use RON 92.
July 25, 2006 @ 2:00 pm
I’m Petronas user so can’t get any RON92, only RON97 Primax3. the additives can let the engine cleaner… can see it when fill into my motorbike. The fuel tank seems cleaner nowadays… wonder its psychological or true… I think newer cars nowadays hv to use RON97. Which country got RON100? hmm…
July 25, 2006 @ 2:11 pm
Many Shell stations in the rural area sells RON92 petrol. In Klang valley it is very rare to see Shell selling it. The only Shell station I came across selling RON92 is the one at Peel Road Cheras. Does that mean Cheras is considered rural by Shell ???
July 25, 2006 @ 2:14 pm
ron100 is available at the pump in japan, but not anywhere elese that i know of. usually the most common is either ron97 or ron98.
July 25, 2006 @ 2:32 pm
Hmmmm…Whopper always pump Esso/Synergy F1 fuel into his Savvy. Been using Esso/Synergy F1 for many years.
July 25, 2006 @ 3:01 pm
In my opinion & from my experiment, comparing the new shell super economy formula with petronas primax 3, as i am driving a myvi, a mvyi has 8 bars and using only 6 bars, driving normally from home to work and vice versa, i manage to travel more than 300km+. With shell super, I only manage 280km+ not reaching 300km.
My rating for all the petrol types in Malaysia:( Higher means less km being traveled with a liter of petrol)
1) Caltex
2) Shell
3) Mobil/Esso
4)Petronas (My fav)
As I am living in penang, theres no PROJET stations here. Does anyone know how PROJET fuel perform interms of fuel economy?
July 25, 2006 @ 3:04 pm
Projet is somewhat similar to Petronas’ Primax when it comes to both power and mileage for my car…
I still like Synergy F1 best.
July 25, 2006 @ 4:02 pm
RON JEREMY?
July 25, 2006 @ 4:39 pm
wheres ron jeremy?
July 25, 2006 @ 4:45 pm
This RON thing hah..or what type of fuel you are using hah..will become pointless when the G raise the fuel price in future
remember MSIAN WE NEED TO SUPPORT OUR g PROJECT OF NEW sPORT cOMPLEX IN lONDON..YES IN lONDON.
p/s usually when Oil company have promotions or new launch fuel they will put in additives, for the first week or two maybe you can feel the different other than that it just a hype.
July 25, 2006 @ 4:49 pm
I use Shell V-Power, used the same in UK, something similar is indeed called Optimax there.
You can get RON100 here, somewhere near the old Subang Airport.
July 25, 2006 @ 4:55 pm
Shell’s just launched a new Super …I wonder if it’s any good..should try…
July 25, 2006 @ 5:33 pm
ShaolinTiger, you sure we can get ron 100 here near subang old airport?? i dont think so la. or are you talking about the Aviation gas thats used for the jetplanes stored there ?
anyways.. if you have a japan import modified car, you can run ron97 and use an octane booster to get the original performance as intended.
July 25, 2006 @ 6:04 pm
honda_driver,
Aviation fuel is usually kerosene, I’m not sure if you want that in your car. hehehe.
July 25, 2006 @ 6:52 pm
To me, all petrol brands feel the same except:
1) ProJET’s Enertec and
2) Shell’s V-Power
These fuels make your car have a more responsive throttle straightaway. And I am a person who don’t believe those so-called testimonials by users in petrol ads on TV.
Only additives that petrol companies add to the base fuel that makes a brand what it is. Think of base oil as rice and additive as adding kicap, chilli sauce, sambal, etc to your rice…
July 25, 2006 @ 8:16 pm
i thought ron 92 is leaded? no ar?
i use ron 92 from mobil sometimes for my tiara…i find it runs smother. maybe old engine design perhaps? but otherwise it is the good oll petronas!
hehe they got cute girls at the counter too..
July 25, 2006 @ 8:55 pm
my experience with ron 95/97 comapared to ron92/93
always go for the higher ron number. gives you more power and more milage no matter what ratings your car is. however if the rating ‘recommends’ you to use a higher ron and you use the lower ron…..you lose both power and milage needless to say smoothness and cleaner engine.
ive tried driving toyota camries for about 800-1000 km. both camry model the same. my friend put in the higher ron one, while i put the lower ron. both car travelled at the same pace and overtaking at usualy similar times as well. both pump to full….when my tank was 20% my friend still had more than half tank. needless to say we continue on using the same type of fuel we started out with. turns out he needs to pump less and fuel costs were lower. over cutting power i think was a bit lacking in my car as well even though with foot down to the metal and weight of car about the same. those figures were for a road trip. and yes, i coudnt beleive it.
for normal driving. i also recommend higher ron. the milage will work out to be about the same for the same cost (even though u get less litres for buying the more expensive fuel). but you will enjoy the smoothness and power more. its more apparent on cars that require the premium oils.
but for malaysia where the difference is 4 cents. i would take the higher one anytime. the diff in australia is 6-8 cents aud. but need to find out what ron is actually in the premium fuel. over here the caltex premium is ron 95 while BP is 98. the shell while is rated at 95 is actually lower than 95. but that was 2 years ago. they might have changed it. its what the petrol attendant told me. shell have a new advertising that says thier fuel formulation has been changed to a type that lasts longer. but if u read the fine print, i think it only specified the test was done on the higher ron one.
July 25, 2006 @ 9:08 pm
things these days r getting complicated .
July 25, 2006 @ 10:42 pm
My campro engine recently keep knocking in the morning after I used Castro Magnetec oil with 10W/40. Previously with Petronas fuel and Shell normal 20W/50 oil and the knocking is occasionally happen in morning.
I feel it not relate to oil or fuel i use, mostly due to the stupid ECU programmer not doing a good job. ^ ^
Not sure what is the latest version of ECU for Gen2? A car with 1 year+ old still can get free ECU change? I feel that service from EON is worst, they normally not willing to do this kind of troublesome job for us…. next time better go with Proton Edar.
July 25, 2006 @ 10:56 pm
err ar u in the wrong topic, lee??
July 26, 2006 @ 12:40 am
leechorwin :
pinging and knocking nothing to do with ECU…u can request for a new ECU flash at any PE service center…its not gona solve much…u either tune it…to get the rite air/fuel mixture ratio thasts set by PDTT(that litle tuning device)..or use a proper semi synthetic oil….go to gen2club n u wil find out castrol is not recomended by gen2 owners…i use shell semi..and its very good..no sound and no nothing..only if i use v-power i wil have slight pinging…primax3 is the way to go….i recomend u go to Proton Edar batu Caves…Very good service…thr r 2 technicians there…who r very good n knowledgable abt campros…thy wil advice u
July 26, 2006 @ 8:43 am
Paul Tan said,
Isn’t V-Power RON97 with additives?
What is the octane rating of Shell V-Power?
The Research Octane Number (RON) is 97.0 minimum and all cars can use this petrol.
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actually RON 92 and 97 have it’s own additive. V power has it’s own special blend additive. V power suitable to a car with turbo engine and engines have high compression ratio. also highly tune engine. all petrol basicaly are the same but how’s it’s been treated and additional additive makes it’s different.
Shaolin Tiger said,
You can get RON100 here, somewhere near the old Subang Airport.
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wah ! what company produce that fuel? my refinery only produce Jet A1 la.
tell me la.
July 26, 2006 @ 9:08 am
Dogster,
ermm.. caltex may not as powerful as primax, but it’s cleaning power still the best… try fill full tank & start the engine in the morning, u can see the difference.. i used to ride my bike more than 150kmp, with caltex my bike vibrate lesser.. i too like primax, but sometimes i fill caltex oso, btw caltex stations r not so many….
July 26, 2006 @ 11:04 am
leechorwin,
ur campro knocking? try change the other varians of engine oil, and spark plugs. its not about ecu. last time it works in my wira, change to no.6 plugs from ngk, the knocking dissapers.
yeah, agree with motorhead, the best cleaning power is caltex
July 26, 2006 @ 11:09 am
Paul Tan said,
Isn’t V-Power RON97 with additives?
_____________________________________________________________________
yes it’s base on RON 97 with special additives
Paul Tan said,
V-Power is called Optimax in other countries and those are RON98, but it seems that our local V-Power is RON97.
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it called RON 98 due to it’s process at the refinery that process that fuel.
July 26, 2006 @ 12:02 pm
i posted this question in monster blog but i’ll post it here too.
is it true that cars like my kancil 850 ex 2001 should be filled up using ptronas’s primax fuel rather tha shell’s fuel. this is an advice given to me by my uncle who’s a mechanical enineer. thanx.
July 26, 2006 @ 12:14 pm
oh ya… i’ve always wanted to know from u guys, as i’m driving a kancil 850 ex 2001, what engine oil should i use? i’m using caltex syn for cars > 1000 cc.
also, if i put one of those huge exhaust pipes, would it really effect my fuel mileage?
sori for out topic q. thanx.
July 26, 2006 @ 4:55 pm
Following Paul’s questions as a guide:-
I use Primax 3. Can get RealRewards points for each Ringgit. Occasionally use Shell. I find that Primax 3 gives better mileage…but I would have chosen Shell if the BonusLink system gives a point for each Ringgit (BonusLink redemption more interesting). So, rewards system plays a big part to me. Fuel difference is quite negligible, I would say.
July 26, 2006 @ 7:36 pm
I used to work in a Shell Refinery that produces petrol. Making petrol is interesting stuff.
July 26, 2006 @ 7:53 pm
Making petrol is one of the most hazardous activities. Petrol contains benzene, which is carcinogenic (cancer causing). It used to be injected with lead compounds to increase its RON (research octane no.) and MON (motor octane no.). Another way was to inject LPG, but only until it reaches its maximum allowable vapour pressure (for storage safety reasons). LPG has octane of 101 (can’t remember exactly).
Anyway, to find out more, you can read about gasoline in Wikipedia.
July 26, 2006 @ 9:34 pm
actually…our petrol ron97 is outdated…some car like frm audis…and alfa wit their new JTS engine…cant accept d ron97 petrol type…can accept but not in d same standard…like alfa gt…when u cruise till 120kph…the engine start struggle a bit…it cost of the petrol…the engine for that car jz can accept the minimum is petrol type ron98…if u wanna ron98 petrol…go for v-power…mahal ma…same goes to diesel…really damn low quality ma…our G had to considerla our petrol…low standardla…
July 26, 2006 @ 10:20 pm
That monsterblog link is not working.
1. I use petronas…for the RR points. Some statins at my area are very generous. RM30-180points. RM50-200 points
2. Support national company, not one coming from the land where drugs are legal, or from uncle sam’s land.
3. Ron 97, though nowdays thast the only option at petronas.
I like Caltex with its reward system. RR has a delayed effect. Clatex you can get drinks right away.
July 26, 2006 @ 10:22 pm
In the UK, the BP Ultimate 102 is RON102.. that can make your car “fly”..
July 26, 2006 @ 10:40 pm
Haahahahaa……. I’m using the best petrol for my Iswara when it comes to “Parking Lot Performance Under The Hot Sun!” Face it, we parked our cars most of the time when we’re in our office. What else.. Esso/Mobil Synergy F1 the best, less evaporated petrol compared to Petronas or Shell.
Power, Milage or RON makes not sense in the parking lot but evaporation does. 0km/h Money Wise Brother… the car is not going anywhere but the petrol does sneaks out! Think about it.
July 26, 2006 @ 10:52 pm
A tighter fuel cap with higher torque would solve that problem..
July 27, 2006 @ 10:30 pm
What Brand New Proton PLASTIC tighter fuel cap with higher torque would solve that problem? Every fuel cap have got holes for controlling fuel tank pressure.. look for it Isamu.
July 27, 2006 @ 10:49 pm
Did I say Proton?
Well, a tighter fuel cap ensures that the seal between the filler neck and the cap is air tight. Less vapour leaked through the the seal would ensure that the pressure control valve work better. The pressure build-up is not always enough to trigger the valve to release the vapours into the air.. Some cars have plastic fuel tanks which allows more expansion thus less fuel loss..
July 27, 2006 @ 10:53 pm
Correction..
“Less vapour leaked through the the seal would ensure that the pressure control valve work better”..
Should read as..
Less vapour leaked through the seal would ensure less fuel loss through the seal.. The pressure build-up is not always enough to trigger the valve all the way to release the vapours into the air..
August 11, 2006 @ 3:36 pm
dear paul-tan,
i have a classic car, Ford Escort. still i can use fuel RON97 unleaded?..because i check from the internet says need to install hardened valve seat. but i check on my manual book, the fuel rating for my engine (ford Crossflow) is 97 but didnt mention lead or unleaded…hm..so how..confuse already.