spring

Valve Spring Coatings

A valve spring’s biggest enemy is heat, and heat is generated in the spring from three sources. First is heat generated by cycling the spring through compression and extension. Try bending a paper clip back and forth, you will feel it get hot at the flex point.  Second is heat generated by the friction between the coils on double and triple springs or the spring and the dampener. Third is heat absorbed by the spring from the cylinder head, especially the exhaust spring being right over the exhaust port. Cooling is achieved from oil being splashed over the spring by the rocker arms.

Many coatings have been used on valve springs.  Most are PTFE based coatings, and this is fine for reducing friction between coils and dampeners, but oil will be shed by the PTFE eliminating any cooling the spring may see. Our S01 Solid Dry Film Lubricant coating is the answer.   S01 not only acts as a superior high pressure lubricant and also attracts oil like a magnet. Valve springs coated with S01 can retain their seat pressure up to three times longer than uncoated valve springs.

Many camshaft manufacturers now offer coated valve springs in their line-up (we should know, we coat many of them), but usually only their most radical springs for all out competition are offered with a coating option. Street cars see just a much benefit however.  By performance standards, a valve spring on a daily driven car is worn out by 40,000 miles.  At this point even though the motor runs fine it will be down on peak horsepower and RPM capability due to the springs loss of tension.  Remember, it is the cams job to open the valve but the valve spring’s job to close it in a timely manner.  S01 is an excellent choice for any motor being built and is very affordable.

For more information call us at 1-800-456-4721 e-mail us at our Technical Department.

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