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**IMPORTANT** Ceramic Coated pistons

7K views 49 replies 20 participants last post by  Topbuzz 
#1 ·
I really need to know whats involved in this process so if you have had it done or know of someone that has had it done please let me know also if there is any gen on other web sites please let me know :)
 
#4 ·
I had my pistons coated with 'Keronite' - similar to ceramic coating but apparently with a much stronger chemical bond between the surface of the piston and the ceramic coating being applied. The claimed benefits over ordinary ceramic coatings are increased durability and better heat transfer allowing higher boost/compression/ignition advance. My Keronite coated omega pistons run in a 12.2:1 compression 1.6 engine, which currently makes in excess of 214bhp, so Im not complaining.

The company you need to speak to is CTG - http://www.ctgltd.co.uk/index.php - tel: +44 (0) 1295 220130. I found them extremely helpful and efficient. They turned around my order in 10 days and only charged me £25 per piston.
 
#6 ·
The claimed benefits over ordinary ceramic coatings are increased durability and better heat transfer allowing higher boost/compression/ignition advance. My Keronite coated omega pistons run in a 12.2:1 compression 1.6 engine, which currently makes in excess of 214bhp, so Im not complaining.
Are you saying becasue of this coating you see better advatnages in doing so? So now the piston heads can handel the higher temperatures, what about the restof the chamber like valves etc, don't they need uprating as well?

So now you have the coating (ie thicker), you MUST have different thickness head gasket to compinsate for the area?
 
#7 ·
Alan - the ceramic layer is only few microns thick - doesn't affect compression ratio. I'm no expert, but I believe that the piston crown area is the most vulnerable to local 'hotspots', which can lead to detonation. Before I had the coating done, I was making exactly 200bhp, but this was on an engine where we were experiencing problems with the oil control rings and where the cams had been swung for maximum torque with a rev limiit of 8000rpm. The rebuilt engine made more power, as I expected revving to 9000rpm, but I was surprised how much more. It's impossible to say just how much of this extra was due to the fact that we were able to dial in more timing advance on what was already a vey high compression engine, but there's probably a few horses in there somewhere.
 
#13 ·
I think the only immeadiate advantage you'll see is with wear resistance. However, ceramic's are generally brittle materials and with the differences in thermal expansion between the ceramic and the cast iron bore there may be problems with cracking etc.
Don't know what effects you would get though from being able to keep more heat in the cylinder due to the coating.
Nikasil (I'm not sure if thats spelt right!) coating the bores is a common method of increasing the wear resistance.
 
#15 ·
Nobody to my knowledge on any engine has ever ceramic coated a bore for the reasons stated above. Other coatings for other reason yes, but not ceramic.

Ceramic coating is about heat transfer and is used on piston crowns. I would think on a LET this would be a good idea.

Give the place above^^ a call and I'm sure they'll give you some gen.

Pourous - who is building your phase 4 engine? Are you having the oil spray bars and modifcations to the big-end shells?
 
#21 ·
From what I can remember, Nikasil is a metal matrix composite (MMC) coating which contains ceramic particles in a nickel matrix.
It provides greater wear resistance, better lubricity and some thermal barrier properties. It is commanly used in motorcycle engines though I believe the yamaha engined ford fiestas have nikasil plated liners.
Like a pure ceramic coating they have sealing problems with standard rings due to the coatings hardness. But the use of "soft" rings ensures correct sealing.
As for plating your cylinders, there may be motocycle reconditioners who can do this - do a search on google or something. You will need to speak to piston ring suppliers to get the correct rings for the coating.
If there are people on here who use motocycles or do moto-x they might know more..

:beer:
 
#22 ·
Right, I thought I dig this thread back up.
I've stripped my C20LET and have cleaned my crowns and have sepreated them from the piston, as below



Now I've found two companies that can ceramic coat the crowns.
But on of them also said the following.....

"Additionally we coat skirt with moly disulphide lube coating to
reduce frictional losses (extra £7) and inside with thermal dispersant to pull heat from piston (extra£4) . Lead time 2 weeks max."

So there you are, does anyone think or have any more gen on this 'moly disulphide lub' or the 'thermal dispersant' inside the crown??

I'm defiantly going for the ceramic coating, just wonderd about the other options.

The C20LET will be running Phase 3.5 with custom intercooler and aquimist once its all back together (engine will have been rebuilt too). Just want to keep the temp cool as possible for max performance before things melt etc
 
#23 ·
Topbuzz...........if your going to coat your pistons why not get the combustion face of your inlet valves coated too? Help keep the intake charge a bit cooler.......
As for the skirt coating............I was tought most of the friction is from ring/bore contact.....ask the company for proof of any gains from this.
:beer:
 
#24 ·
> why not get the combustion face of your inlet valves coated too

Hmm...wonder if this would help at all. I know the exhaust ones are sodium filled, to help dispate heat, so ceramic coating them help.

Then again where is it disaprating heat too? The metal valve in contact with the valve guide (and hence the head) maybe acting like a big heat sink. So the cermaic coating my actual be an isolator for that. Don't know, I'll ask them.
 
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