I have heard this question asked severally, “Should I use V-power or Excellium”, so here is the breakdown of what you should use and when to use it.
Total Excellium
This it Total’s once “premium” petrol but now their mainstay. The term Excellium is simply marketing jargon for additives that they add to the fuel. The major additives are detergents that help in cleaning out the carbon from your engine. Anyone who knows anything about engines will tell you carbon is very bad for engines and it degrades engine performance over time by clogging up it’s components, kind of like cholesterol does to your veins.
Excellium works well for most vehicles in Kenya but not all. The difference is in the fuel injection method. With port injection, fuel is sprayed to the back of the intake valve and together with the added detergents, carbon is washed away from the valve. With Direct injected engines, fuel is sprayed directly into the combustion chamber therefore the additives do not get to clean the valves and only the injectors would remain carbon free. With carburated engines, the cleaning effect is much more given their tendency to accumulate carbon rapidly.
Shell Fuel save
This is Shell’s regular priced fuel that has additives that “reduce energy losses” in the engine. This is tech-speak for lubricating properties to reduce friction in the piston rings therefore raising the efficiency of the engine which reduces how much fuel the engine burns. The fuel saving characteristic here is marginal and will vary greatly depending on vehicle and driving conditions. It will also only work as intended for a vehicle with a modern electronically timed and fuel injected engine running perfectly. So any engines with variable timing will benefit as long as all the other components are properly serviced and in perfect working condition i.e spark plugs, coils, air filter, etc
Shell V-power
This is Shell’s premium fuel that has 2 major benefits. It has cleansing additives similar to Excellium and has higher octane rating of 95 RON over regular fuel’s 93 RON. The octane rating is a measure of how difficult a fuel is susceptible to ignition and is mostly determined by additives to the fuel. These are what replaced the Lead in “Unleaded” fuel to prevent pre-ignition, commonly known as “knock”. Apart from the cleaning additives mentioned above in Excellium fuel, the higher octane rating is only usable by high compression engines and forced induction(turbo/supercharged) engines. If you don’t have a turbo or supercharger, it’s almost always not worth the extra cost unless you have a high compression engine e.g 12.5:1 in the Toyota GT 86.
The biggest problem with Shell fuels is the adulteration by individual station operators who may mix regular priced Fuel save with V-power to make bigger margins on the premium price. It’s therefore advisable to find a petrol station you trust and always fill up there. An easy way to figure out if you have good fuel is by looking at the variable timing of your engine especially under load. Best case scenario is your ECU advances timing which shows it’s happy with the fuel and no detonation is occuring. If the ECU is retarding timing upto -1 degree, that’s also acceptable but anything around or more than 5 degrees is probably a bad fuel issue(assuming your spark plugs and coils are in proper working condition)
Conclusion
So in summary, always use Excellium whenever possible as it will increase the longevity of your engine and save you fuel over the long run because of an efficiently working engine. Fuelsave only marginally saves you fuel but doesn’t help increase the longevity of your engine. V-power does cleans regular engines and enables high performance engines make more power by adding more compression via boost and advancing ignition timing.
Fuel sold in Africa is of the lowest quality due to its high sulphur content (from countries like Iran) called “Dirty Diesel” / “African grade”.
Even West African countries export the highest quality of crude only to import the lowest quality of Fuel.