What happens when you mix 93 and 95 petrol?

Answers. Hi there, It won’t cause problems if your car isn’t fitted with a turbo- or a supercharger, but if it is equipped with either of these, it’s definitely better to always use the highest available octane (95) to ensure that the engine won’t get damaged. Use what the manufacturer recommends.

Before we delve into LRP and unleaded, it is important to understand how we got to unleaded fuels. Cars manufactured prior to 1992 were designed to run on petrol containing lead. Lead was used in fuel to reduce engine knocking, boost octane levels, and improve the daily wear and tear on the valve seats within the motor. Research began to find, however, that there was a cumulative toxin within the fuel that was dangerous to people as well as the environment. It was, therefore, ruled that leaded fuel was in fact a dirty fuel and it was slowly removed from the market. While the reduction of lead in fuel began in the 1970’s, phasing out only began in the 1990’s. South Africa officially phased out leaded fuel in 2006 and introduced LRP. LRP was the “healthier alternative” to leaded fuel, and allowed older engines, which are incompatible with unleaded, to stay on the road. Instead of previously used tetraethyl lead, LRP uses potassium compounds. These buffer soft exhaust valves and seats to reduce the amount of wear.

South Africa was one of three markets, including the UK and Australia that used LRP as an interim alternative to leaded fuel. Most countries simply transitioned straight to unleaded. Despite LRP being phased out internationally, 20% of South Africans are still using this fuel. Currently only 1-2% of cars actually need LRP. It is expected that by the end of this year, we will no longer have the option of filling up with LRP. Fuel stations all over the country are beginning the transition to Unleaded and Diesel dominated pumps. With the phasing out of this fuel on the cards, there needs to be more education around unleaded fuel. There is a lot of confusion around the use of LRP versus unleaded, as most people don’t realize that their vehicle can in fact operate on LRP.

Many people who own cars older than 25 years old are weary of transitioning to unleaded. The biggest concern lies around valve seat recession, which is essentially just the acceleration of valve seat wear and damage. There are options for classic cars to use unleaded and stay on the road, however, including modifications and additives. It has, in fact, been advised by BP that all cars manufactured from 1990 onward are able to operate on unleaded Fuel.

Scroll to Top