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.

Read more: http://paultan.org/2006/07/25/research-octane-number/#ixzz0STa71OIa
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AUG 31 – Salaries can only be increased so much (and increases usually occur only once a year!) and belt-tightening also has its limits so everyone is looking for ways to reduce their cost of living. For people with cars, the cost of motoring can be a significant chunk of their monthly expenditures and therefore keeping it down is helpful.

The big jump in fuel prices last year certainly made motorists more conscious of the need to economize on fuel while driving. Studies have shown that many motorists still waste a lot of petrol due to long periods of idling, eg while waiting for the kids to come out from school, and of course, not keeping the engine in proper tune also causes fuel consumption to be higher.

While it is possible to save fuel by modifying driving styles and perhaps using the car less, the petrol you buy doesn’t offer many alternatives as prices are fixed by the government. Two grades have been available all this while – RON92 and RON97 – the former grade retails at a lower price.

From September 1, 2009, the government has directed that RON92 be phased out and replaced by RON95. The move will see the RON95 price per litre going up by 5 sen compared to RON92 but it will be cheaper by 5 sen too compared to RON97. At the time of writing, it is presumed that RON97 will see a price increase as the government subsidy will be reduced if not stopped.

The move to RON95 will benefit many motorists whose vehicles do not really need RON97 petrol and can run just as well on RON95. The switch will save them money without having to even alter their driving styles, modifying the engines or sacrificing driving pleasures.

While the difference of 5 sen per litre from the RM1.80 price of a litre of RON97 may seem small, think of the total savings per full tank of, say, 60 litres and that will come to RM3.00. If you think of it in terms of a Malaysian breakfast, that could get you a packet of nasi lemak and a drink!

So switching from RON97 to RON95 will save you money right away and if you choose your petrol brand thoughtfully, you can even save some more in the long run. Caltex Premium 95 with Techron®, a RON95 unleaded petrol, can help you save more money in your pocket by keeping your engine running at its best all the time with the Techron® additive package which provides a highly effective clean-up of the fuel intake system as well as the fuel injectors or carburetors. And if you keep using Caltex Premium 95 with Techron®, it will keep your car engine clean and running efficiently.

Most modern cars can use RON95, among them Proton and Perodua models, all locally assembled Honda models and even the latest models like the Nissan Sylphy and Chevrolet Optra. You should check the Owner’s Manual or ask the company that sells your car whether the engine can run on RON95 and if it can, then you’re in luck and can get a further ‘rebate’ on your petrol purchase!

Contributed by Chips Yap, editor of the Motor Trader website for Caltex.