You might have seen numbers like RON97 and RON95 at your neighbourhood petrol station. Fuel with a RON97 rating is more expensive, RM2.40 per liter at time of writing with the lower RON95 rating going for RM1.90
Have you ever wondered what they mean? Why is RON97 more expensive than RON95, and can you use RON95 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?
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 RON95 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 RON95, 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 RON95, you might as well pump RON95 fuel and save abit of money since RON95 is much cheaper. 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 RON95 petrol and decide to save abit of money, go ahead. Buy me a teh tarik with the money you save!
Which RON 95 petrol is the best? A details comparison studyI know many of Malaysian motorist are complaining the lack of performance of RON 95 petrol since RON 95 has displace RON 97 petrol as the main stream petrol. RON 97 is now the premium petrol. Since RON 95 is RM 1.80 per litter from 1st September 2009 and RON 97 has increased the price to RM2.05 per litter, most of us has to tolerate with lower grade petrol due to budget constraint.Ironically, many developed countries do not sell RON 97 petrol. In Singapore, only RON 92, RON 95 and RON 98 petrol are sold.
I do not want to compare RON 97 with RON 95 petrol. No point actually. Even you are complaining but you will still using RON 95 due to the lower price. So, my study is comparing different brands of RON 95 petrol.
Car: Proton Iswara 1.3 Manual, year 1999
Route: KL, PJ, Shah Alam with almost 100% city drive.
Driving style: economy driving. Seldom press the pedal hard except overtaking. Not a racer
Note: Each time I will fill the petrol until full tank
1. Brand:BHP Infiniti 2x
Total cost: RM56.81 or 31.62 l
Fuel consumption: RM0.127/km or 14.16km/l
Remarks: Quick, smooth during gear transmission (from low to high). Engine noise is OK, not noisy but you still can listen it. It is exceptional when pick up. I am satisfy with it.
2. Brand: Caltex Techron 95
Total cost: RM55.94 or 31.07 l
Fuel consumption:RM0.123/km or 14.68km/l
Remarks:When I start my engine, it is very quiet. It is quiet and smooth even during the low gear transmission. Engine noise is lower than BHP infiniti 2x. It is powerful when pick up. Almost as powerful as BHP petrol. No noise even at 110km/hr. A better fuel consumption as well.
3. Brand: Shell Super 95
Total cost: RM51.71 or 28.728 l
Fuel consumption:RM0.117/km or 15.336km/l
Remarks:I have change a new set of tires in this study. This is a very bad experience using Shell. The engine is very noisy even when I started my car. The noise of engine is noisy and rough when changing gear. Most remarkable is I hardly pick up to 110km/hr as the engine is so noisy. I will avoid using this fuel. I will reserve my view of fuel consumption as different set tires is used.
4. Brand: Petronas Primax RON 95
Total cost: RM50.41 or 28.006 l
Fuel consumption:RM0.123/km or 14.618km/l
Remarks: Ordinary pick up but much better than Shell. I still heard some noise form engine when I start my car but it is acceptable level compare with Shell. Easily pick up at high gear but lack of power in low gear. Transmission is consider smooth. Surprisingly even it is more powerful than Shell, the fuel consumption is higher.
5. Brand: Mobil Synergy 5000
Total cost: RM63.17 or 35.093 l
Fuel consumption:RM0.113/km or 15.879km/l
Remarks: Good pick up and transmission from low gear to high gear.The engine noise is the second best just behind Caltex Techron 95. The fuel consumption is surprisingly better than any of the fuel in the market. I can not complaint anymore of this.
Since I have change my set of tyres during the test, I retest Caltex Techron 95 to cancel the tyre effects. The prurpose is the feul consumption.
Retest of Clatex Techron 95 with new tyres give me 14.6km /l which is even less than the first test 14.9km/l. I would said the new tyres on the fuel consumption is negligible.
Testing finished on 1st Nov 2009.