clikel

Here is a list of coatings and Cryogenic processings that help piston engines that I copied from numerous websites to help those who are not aware of the coating process out there. For those who do know; just ignore it and help with the quesions.



I have 4 questions and yes it all can be done, but what reason for or against it are my questions:



1. The rotor compression face coated as done to the top of a piston to help fight against detonation and keep more thermal energy driving the rotor instead of absorbing into the rotor?



2. The sides of the rotor and housing could be coated like piston skirts or would that flake off or interfere with sealing?



3. The exhaust ports could be coated as well as the exhaust housing of the turbo and exhausts system to help the velocity of the exhaust gases stay higher?



4. Cryogenically process the rotars and housings, maybe the Apex seal 2mm Seals & springs?



====Basic Info====



Rotor and Rotor Assembly Modifications



http://www.hayesrotary.com/page12.htm

MOS2* Treatment to Rotors

Rotors and rotor main bearings are treated entirely with MOS2*, the compression dishes are impregnated with a ceramic coating, and the rotor oil cavity is treated with a high heat transferring coating. The coatings are capable of withstanding temperatures over 1800 degrees Fahrenheit and maintaining excellent adhesion during rapid temperature changes. This combination allows for reduced friction, dispersion of combustion heat, and less retainment of heat. This results in better long-term functioning of rotor seals, increased utilization of fuel, less stress on apex seals, and virtually no carbon build up over time. Recommended for all engines but especially high performance racing applications. PER-400



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PISTONS - Piston tops are coated with CBC2, a Ceramic Barrier Coating which provides a layer of thermal protection to the piston tops. This highly polished coating greatly increases part longevity as it reduces heat and detonation.

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PISTON SKIRTS are coated with TLML, a “Moly” dry film lubricant which provides the piston with excellent lubricating qualities. TLML will provide lubrication protection during momentary loss of oil film and reduces friction as part temperatures decrease.

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CYLINDER HEADS - Combustion chambers on either cast iron or aluminum heads can be coated with CBC2 or CBC3. This coating will help increase thermal efficiency which will produce more usable power. Exhaust flow is also increased when using TLHB on the exhaust ports of the head.

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Pistons and Valves



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 film (SDF) 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. Thermal barrier coating is 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 HPC S06 is a solid dry film lubricant that 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 PTFE. 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. PTFE 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. S06 can also be applied to the stem of the valve to reduce friction and wear. Engine bearings are another excellent application for HPC's S06 coating.



---Cryogenically processed

Race teams have found deep cryogenic engine processing to give them an edge on the competition. With the engine components cryoed they can save money on parts and run more on the edge without constant fear of burn down or breakdown.



The advantage that the cryogenic process brings is a significant increase in abrasive wear resistance and durability. These are accompanied by increases in tensile strength, toughness and dimensional stability coupled with the release of internal residuel stresses.



Cryogenically processed motors and othe components have less vibration, less burn downs and less distortion. Treated piston rings seal better against treated cylinder walls reducing blow-by equaling more HP and torque. Race car brake rotors see a 3-5 time life increase after cryo, resisting cracking and warping. Cryoed brake rotors also result in a much longer brake pad life.

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j9fd3s

1. i think its not a good idea, as heat in the spark plug area of the rotor housing is already too high. if you block the heat going into the rotor its gotta either go into the coolant, or out the exhaust, which are already hot. this is my opinion, and i have no facts to back it up



2. dunno, it might. friction between the rotor housing and apex seal is important. in the old days when they had different apex seal and rotor housing material you could build a motor that would peel all the chrome off the housing in about an hour. who knows if this coating will be compatible



3. yes, good idea. coating will eventually burn off



4. dunno

dgeesaman

All IMO. I've done a lot of research on the cryo subject and applied my engineering knowledge to draw a few conclusions.



1) Not sure. Ask to see a coated rotor after being removed from an engine with a lot of miles. If they can offer proof showing the coated rotor is very clean and without buildup, I would consider it. However, they can't prove the 'thermal performance' is any better (I know of no test that shows the degrading effects of carbon buildup in a rotary, which is what you would gauge it against). This may be a convenient fact if they make this claim, since you can't prove them wrong. Unless the process is cheap, I wouldn't bother.



2) I don't know if the coating will hold up, but it won't provide any performance or longevity improvement i can think of. In fact, if any coating flakes off you could damage seals and that's real bad.



3) Maybe it will work, but probably negligible effect. I would ask them about the thermal expansion of the coating and how closely it matches steel - if it does not, the coating will peel away and end up downstream.



4) Cryo process the rotors, rotor housings = excellent idea. The improved dimensional stability and wear resistance will help. Make sure you have the parts dimensionally checked after the process. Heat treatment of small parts like apex seals and springs is usually pretty well optimized, so treating them is probably a waste of money.



Fortunately you've picked some reputable cryo source. When I searched for it I turned up nothing but foo's looking to cryo as many things as possible, and know nothing about it. Cryo your keychain if you let them.



Dave