Since I've had the car it's been run on normal Shell Fuelsave stuff. Decided to have a change today and filled up with BP Ultimate instead. My God! Can't feel any extra power but she no longer sounds like she's going to fall to pieces in the morning. Much, much smoother and quieter both on a cold and hot engine. If your car lives on the normal Shell stuff and feels rough, stick a tank of BP in it, see how it goes.
Only other thing mine gets is 350ml of 2 stroke in every full tank.
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