The following are test results on two samples of motor oil formulated for use in classic cars, muscle cars and other older model vehicles with engines that have flat tappet cams, lifters & pushrods. These products contain higher levels of the antiwear additive ZDDP than that in motor oils formulated for use in most cars currently on the road. For more about such motor oils, see PQIA article, Motor Oils for Classic and Vintage Cars.
n addition to the two motor oils designed for use in classic and muscle cars, the third in the set below is MPT Thirty-K. This product is labelled as “Advanced True Synthetic Lubricants, formulated with 100% synthetic POE-PAO, basestocks for extended oil change intervals.”