Tool Steel flat tappets are replacing the standard cast iron tappet as the product of choice for the discerning racer. Their use eliminates exceptional wear due in part to the lubricating oils available today.

Why Tool Steel Flat Tappets Run Forever

Text by Jim Mozart
Photos by Moore Good Ink

Despite the popularity of the roller tappet both in a mechanical as well as hydraulic setting, typical flat tappets, also known as lifters or followers, are still as popular as ever. While a roller tappet utilizes a roller to roll along the camshaft’s lobe profile, a flat tappet simply rides directly on the lobe. To eliminate wear, the base of the flat tappet is ground on a convex shape and the cam lobe is tapered. The combination of the convex shape—which is almost indiscernible to the naked eye—and the tapered cam lobe forces the flat tappet to spin in the tappet bore of the engine.

As opposed to a flat tappet, a roller tappet; also known as a lifter or follower; utilizes a roller to ride against the cam lobe. Due to the roller’s design, tappets are held together by a tie bar to keep them straight in their bores; in contrast flat tappets must spin.