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Message: <blockquote data-quote="wc9922" data-source="post: 322120" data-attributes="member: 6000">The performance of a gasoline blend is not just hinged on the RON  alone (research octane number).The RON number only indicates the fuel performance under predetermined load test prescribed under ASTM 2699 testing method requirements. RON number usually gives an indicator of the fuels characteristic under constant load conditions in 4 stroke engines, i.e simulating cruize or low load conditions.Another fuel performance indicator is called MON ( motor octane number) prescribed under ASTM 2700 test testing requirements. MON test are involves more severe varying load test conditions  giving an indication of the fuels performance characteristics under severe load conditions.  The higher the numbers for MON or RON just means the fuel have a higher knock resistance capability for the control test conditions benchmarked to pure components. Usually MON numbers are lower than RON numbers. What is important is the average of the fuels RON and MON numbers which give u another term called OCTANE NUMBER = [RON+MON]/2.  But they never tell u the Octane Number of the fuel, do they? Nor do they tell you the MON.  So in the case of V-power, It may still have l have the same RON of 97 as the ' Super'  but it may have a MON rating higher than Super so overall u get a higher OCTANE NUMBER rating. That is why with V-power u may sense u do get the performance as well as some fuel economy on the side. But this is only apperent on cars that run under closed loop ECU control. Gasoline specs are very complex/secret also as the composition (% by volume) of gasoline are consist of many HC compounds such as oxygenates, paraffins, reformate, isomerates, aromatics, olefins and benzenes.These does not includes the additives.  U change something u change the RON and MON as well as other thinngs like vapor pressure etc.But generally have to fall within a certain range of ASTM test values to be classified as  UL92 or UL97 grade for the market. I can tell u the gasoline base stock for V-Power and Shell Super is different. Shell Super grade is refined in Port Dickson refinery while the V-power base gasoline is imported from Shell Singapore Bukom refinery. Shell PD's refining operating mode/process technology is not able to produce a final mogas blend that matches  V-power's base composition requirements at present.  The additive package for Super and V-power are different as well. This is normally injected at the truck loading area of the refinery before heading out to the petrol stations. So I hope this would enlighten you guys to why V-power cost 50sen more than Super while u think the RON number is the same.</blockquote>

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