Federal-Mogul Adapts Heavy-Duty Valve Tech to Cars

Federal-Mogul LLC is introducing a smaller version of the Rotocap valve rotator, which was designed for commercial trucks, to use in passenger vehicles with low-revving, four-valve-per-cylinder engines.

At high speed, an engine’s intake and exhaust valves rotate within their guides, which evens out wear and heat distribution. The function of the Rotocap is to control rotation at low engine speeds, when spring torsion and resonances can cause uncontrolled movement. The device introduces a defined angular movement when the valve opens.

Federal-Mogul describes Rotocap as a compact arrangement of balls and ramps within a self-contained assembly. The product has long been used in the heavy-duty sector, where engines often run too slowly to generate consistent valve rotation on their own.

The need for such systems in cars and light trucks is growing as carmakers move toward smaller “downspeed” engines used to boost fuel economy, coupled with increased stop-and-go city traffic that cause engines to operate for prolonged periods at low speeds.

Rotocap also reduces abrasive wear of the valve seat area because it rotates the valve after it opens, not as it closes. This is expected to be especially helpful in engines designed for reduced oil consumption and alternative fuel systems, which can have a greater wear potential than gasoline or diesel engines. Federal-Mogul says hybrid-electric vehicles operating with a low rpm range also can benefit from the technology.

Federal-Mogul will display the automotive Rotocap next month at the Frankfurt auto show.