Q2 How will I know if my car needs Valvemaster? Typically most cars built before 1981 and many built before 1986 were designed to run on leaded petrol. If you are not sure whether your car needs a VSR protection additive the motor vehicle manufacturer can be contacted for advice. Where lead replacement petrol is available, the petrol companies have conveniently pre-mixed the petrol with the VSR protection additive. You will only need to buy Valvemaster for additional protection for very severe driving conditions, as described in Question 6.