Octane Booster increases the RON octane rating of both lead-free and leaded petrol. This has a positive effect on engine performance. It also reduces the risk of the engine 'pinking' and provides a protective layer on the valve seatings with less risk of costly engine damage. Octane Booster is suitable for both 4-stroke and 2-stroke petrol engines and is safe for use in combination with catalytic converters and tuned engines. The maximum dosage for best results is one bottle of Octane Booster to 20 litres of petrol.