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Old 03-09-2008, 12:27 PM   #1
Davenow
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Default Dropped the cash for coatings on my new pistons. Convince me it wasnt a waste of $$

Ok so I know that a lot of people recommend it.

A lot of people recommend a lot of crap that doesnt do anything, or does very little.


That said, I know there has to be a reason they recommend it.



So, does it REALLY make that much of a difference? What exactly does it accomplish?


Does the coating on the dome REALLY make the piston hold up better?

Does the coating on the dome REALLY make more power like some coaters claim?

Does the side coating REALLY make the piston slide easier?

Does the side coating actually make more power like some coaters claim?

Here are some pics of one of my new sexy pistons BTW. CPs coated by CP.


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Old 03-09-2008, 01:40 PM   #2
flstffxe
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So, does it REALLY make that much of a difference? What exactly does it accomplish?


Quote:
Does the coating on the dome REALLY make the piston hold up better?
Yes, it acts as a heat barrier and can protect it from short term damage caused by ping/detonation.

Quote:
Does the coating on the dome REALLY make more power like some coaters claim?
Not really, it can however help to cover up signs of a bad tune, detonation. With a proper tune you should be able to achieve the same #s on the dyno with or with out the coating.

Quote:
Does the side coating REALLY make the piston slide easier?
Yes, it adds a solid layer that acts as a sacrificial lubricant. It also fills in minor imperfections in the surface of the pistons making the even smoother.

Quote:
Does the side coating actually make more power like some coaters claim?
No, it does not "make" more power. It can however help to reduce friction, reducing friction frees up power lost to internal drag. In turn this does show up as higher # when you get to the dyno. Are you making more power, no. you are just not wasting it in the engine its self.


The gains seen from the coating are minimal. However the protection they offer should some thing go wrong, say un-metered air entering your intake that could cause a lean condition that can potentially have damaging effects is a benefit. It can give you enough time to locate the issue before destroying a piston.
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Old 03-09-2008, 01:41 PM   #3
xerox445@yahoo.com
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They look sweet....lol

If you don't bust any ringlands if the car is detonating, it wont melt through the piston.

You should have a tighter piston to wall clearance with the side coating, with less friction.
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Old 03-09-2008, 01:49 PM   #4
Defiant Autospeed
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They claim it makes it hold up to detonation better as well.

Does it? I would think that the thicker top ringland and the special shape to the second ringland would do way more.
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Old 03-09-2008, 02:37 PM   #5
wrxhard
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I read an article in engine masters challenge about how all of the top competitors used a ceramic dome coating on the pistons. An interview with one of the builders said he used the coating because he built his motor to be able to take detonation. He literally set it up to detonate under certain load conditions so it could make the most power at others. This is a naturally aspirated v8, so it doesn't DIRECTLY corelate, but an IC engine is an IC engine ya know and strength is strength, so alittle bit does... maybe???
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Old 03-10-2008, 11:37 PM   #6
charliew
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Coated pistons have been used a long time. Even harley coated the skirts in their motors more than 12 years ago, mainly to slow piston wear and make them quieter. If the tractors of motorcycles thought coatings were important and spent the money on it you can bet it helps. Coating the tops also helps keep the heat in the combustion chamber and out of the piston. This was a reason subie used squirters, to keep the piston temps. managable. Are you also going to coat the combustion chambers to also contain the heat? There is no reason to allow any motor to detonate as there is never going to be a coated piston built to withstand detonation. Thats what engine management systems are for. Coatings lower oil temps. and allow more timing by controling heat better.
Charliew

Last edited by charliew; 03-10-2008 at 11:43 PM.
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Old 03-10-2008, 11:53 PM   #7
flycaster
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Heh, what needs a "coating" is that poor guys head. Jeeze, tell him to put a hat on.
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Old 03-11-2008, 12:53 AM   #8
Chi_San
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Quote:
Originally Posted by flycaster View Post
Heh, what needs a "coating" is that poor guys head. Jeeze, tell him to put a hat on.
Aww, it's just a little sunburn.

Ceramic is tough stuff, and it's great at reducing friction. A ceramic RX-7 motor typically holds up better than a non ceramic motor.

Another option I can think of when building my motor.
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Old 03-12-2008, 09:55 PM   #9
Davenow
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Im going to call swaintech about coating the combustion chambers, it depends how much $$$$ they want. I am hitting the wall on this build financially.
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Old 03-14-2008, 12:25 PM   #10
cnstman
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how much does CP charge for their coating service?
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Old 03-14-2008, 02:54 PM   #11
manxaru
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I'm having my coatings done at Polydyn - http://www.polydyn.com

I believe they charge $22 for piston crowns, $38 for complete pistons and $33 per combustion chamber, including the bottom of the valves.

Since the turbo shows on my car, I'm also having the exhaust housing done, which keeps it looking good and holds in a little more heat.
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Old 03-14-2008, 03:36 PM   #12
sama lama
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It should reduce friction on pistons an cylinder walls and short skirt pistons create more friction. It should reduce oil temps especially on long high boost events.
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