HPC Piston and Valve Coatings

HPC offers two coatings for pistons and valves that can be used together separately of each other based on needs and some class regulations in racing. HPC's thermal barrier coating (TBC) is applied to the combustion face of the piston and a wettable solid dry (SDF) film applied to the skirt.

Probably no part of an engine undergoes greater thermal shock than pistons and valves. Yet this has no effect on the bonding properties of HPC's TBC which has the same coefficient of expansion as aluminum. Particulates are bonded with an inorganic binder which is unaffected by petroleum products. With a bond strength of 10,000 psi, this coating's non-porous ceramic matrix improves flame travel and combustion efficiency as well as reduces oil temperature and prevents carbon buildup. HPC's TBC process also prevents excessive heat from reaching the piston rings reducing radial tension loss due to the ring overheating. TBC applied to the combustion face of the valve prevents overheating of the exhaust valve and heat transfer from the intake valve to incoming cool air and fuel, thus providing a denser air/fuel charge. The process works equally well on both two-cycle and four-cycle pistons, and is applicable to new and used parts.

Our S01 is applied to the skirts of the piston to reduce friction and prevent scuffing. This wettable matrix coating is a Molybdenum Disulfide based coating rather than Teflon. Moly is a higher pressure lubricant and does not "cold flow" under pressures exceeding 150,000 psi. Also Moly attracts oil keeping an adequate film of oil on the part. Teflon will shed oil and thus becomes the only lubricant between the piston and the cylinder wall. The Moly is suspended in a thermosetting polymer binder which hardens during curing providing a permanent lubricant unlike break-in Moly sprays. S01 can also be applied to the stem of the valve to reduce friction and wear.