Ceramic Coated Supertech Pistons
 

Hi all,

Just wanted to share some pictures of my Supertech 10.6:1 pistons that I received back from Calico coatings. I know a few guys on here are running coated pistons but I didn't see a thread with photos or a personal review.

Turn around time was fairly quick, sent everything out and got it back in about a week, and staff were very friendly and followed up with my order and to see if I was happy with what I got.

Tops have been coated with a ceramic coating, their CT-2 Thermal barrier coating which used to be copper in colour. I was told the change was simply in colour and its the same stuff they used to offer.

https://www.miataturbo.net/attachmen...ine=1386493883

Piston skirts were coated in their CT-3 dry film lubricant coating. I was told that this is essentially the same coating used on Mahle pistons with added teflon. This stuff is seriously smooth, running your hand over it vs. the factory Supertech coating there is definitely a difference.

https://www.miataturbo.net/attachmen...ine=1386493883

Just on a side note, has anyone had similar finishing on their Supertech pistons? I had quite a few nasty burrs on the inside from the drilling process. Can't help but relate this to the price though, cheap pistons will have cheap finishing I guess. Nothing a dremel can't clean up but that sort of defeats the purpose of buying a quality product.

https://www.miataturbo.net/attachmen...ine=1386493883

Unfortunately didn't notice these burrs until AFTER I had sent them out...:vash: This was by far the worst burr I had seen. Sent an email to Supertech but of course didn't get a reply hah...

https://www.miataturbo.net/attachmen...ine=1386493883

Hopefully should have results to post back to this thread after a few months, machine shop has a backlog of work and won't get my block until early spring at the earliest.

Even though your pictures don't show I had a similar experience with ST not smoothening the edges after machine work. My 11:1 pistons were sharp enough to cut paper.

I got the top coating on my CP pistons but not the skirt coating since I was advised that it wears off eventually anyway - made sense to me and saved me some $$$.

how much? wish i could see pictures!

I sure wish this forum would get its act together with regard to inline images. Just let us host our own damn images and this wouldn't be a problem anymore.

This may sound totally stupid, but I noticed this too when I went to this site from my mobile phone. What gives?

EDIT: Pictures added, although I still don't understand how I can embed them into the post.

Anyhow,

I paid about $160 for 4 pistons, that price includes both the thermal barrier and dry film lube. Pretty reasonable if you ask me.

I talked to Dave @ Calico over the phone as well regarding piston skirt coating as well. Although in theory the skirt does "wear" and the coating will eventually be gone in the long run, its also the area where the coating is supposed to show the most effect as well. The reduction in friction should theoretically help improve power as well as keep the area around the skirt much cooler. He said that if anything, he would chose to get the skirts coated over the piston tops if he only had to pick one. I guess this assumes that you chose to use a clearance which is reasonable so that the skirts aren't rattling up the bore (another topic to be discussed) and in turn scraping off the coating faster than normal.

Reasons that I went for a coated top was that a friend of mine saw huge improvements in his 700whp Subaru STI using coated pistons. Keeping the heat where it should be helped keep things more reliable. If I had the budget I probably would have tried thermal coating the combustion chamber as well as the valves.

How many useful hours on the Skirt coatings? 10, 20, 50, 100?

I wonder how many hours till the ceramic paint is burnt off; 5, 10?

I had someone come in with a properly done ceramic coated downpipe that had a crack for me to repair with my TIG.

I couldn't grind the ceramic out of the downpipe. even if I ground off the color, it still wouldn't weld properly...the ceramic was blasted right into the parent metal.

Since then I have total respect for proper coating like the OP has done.

Yeah I'm not looking forward to having to fix any of my swain coated hot parts. I wouldnt worry about it if it was a coating like the op, welder would burn it right off without needing to grind.

See the photos I've attached and you be the judge.

Pictures speak a thousand words. These pistons were put into my friend's STI and were pulled out after 10,000miles after an unfortunate event when his meth didn't spray.

As you can see, piston tops look like they are almost brand new. Its not a "paint", its a coating as previously mentioned by schlammed. I'm not sure why your Swain coated parts would hold up any differently than Calico coating. "welder would burn right off"... umm yeah. Goodluck with that.

For an actual answer of how well the coating will hold up, well YMMV. Everyone's situation is different. These were taken out of a car running a much larger bore and clearance, much higher boost than most people here see and making much more power as well.

Those look like they're missing a whole lot of coating, especially on the exhaust side of all but cylinder 1. The might actually have no coating at all and all the brown color could be carbon and smutz, but I'm giving the benefit of the doubt.

Actually if they had no coating at all they would be shiny, like in the picture shown below. Exact same pistons except uncoated.

Still curious why you think your swaintech coating is any different than how these pistons are coated. :dunno:

I would advise to stay away from Swain tech! One of the festiva guys did the swain tech here are his results
I just recived my b6 pistons back from swaintech, they are pretty! I had them do their "gold coat" top coat and their "pc-9" skirt coating. Grand total with shipping..... $228.88! If your thinking of doing a build read up on their site, there is A LOT of very technical articles and magazine excerpts that back what they claim. I hope they do what they claim. Swain Tech Coatings | Industrial Coatings | High Performance Racing Coatings | Technical coatings to solve problems of heat, wear, corrosion, and friction
https://www.miataturbo.net/attachmen...ine=1386644485

after 20k
https://www.miataturbo.net/attachmen...ine=1386644401
After less than 20k I had a loss of compression on #2&3, smoking and excessive blowby. #2 had 90psi dry and 172psi wet, #3 had 70psi dry and 185psi wet. Tore the head off to diagnose, and this is what I found. Not very happy right now.

Never had a antifreeze leak. It was running great till about 3 weeks ago. It had just the tiniest puff of oil smoke on start. Also it seemed to want to have spark knock, where as it never had at the timing settings it had the whole time this engine has been in the car (2 weeks before madness). The intake side has seemed to take all the abuse. It almost looks as though the fuel mix has eaten off the coating. The small holes in the center were there out of the box. The head and block mating surfaces aswell as the head gasket (cometic) look great. If you look closely at the pattern of the bare sections, it follows the shape of port swirl. I haven't pulled them out to see how the skirt coatings have held up, but it looks as though the top coat, erroded and causes that side of the pistons to overheat locally causing the rings or possibly the pistons themselves to fail. The walls look great, they all had beautiful cross hatching and a few very minor vertical scratches, that don't catch your nail

Yes, it was definitely a coating failure that caused all the detonation that damaged the pistons/rings. It certainly wasn't detonation that blew apart the coating and caused a bunch of damage to the pistons and rings.

:rofl:

My thoughts exactly...

Savington you beat me to it- Though I'm more familiar with detonation degradation in two stroke motors (jetskis, they like to eat themselves) detonation almost always eats the piston/ringlands at the exhaust ports... What did they do here to make it manifest on the intake side?

L O L...

Just pulled my head recently after 20 something thousand miles... Swain coated pistons still look great.

Bump from the dead, these pistons are now in my block. Haven't started the car yet, but I came across some interesting stuff.

According to Calico's site the coating should vary from 0.5-2mil thickness after it's applied. When the block came back it was decked 0.003" for resurfacing. I have the 10.6:1 B6 pistons. I was told that these pistons now protrude past deck height at about 0.0013+. This seems about right given the thickness of coating and the amount that was taken off the block.

When I measured the pistons in a laboratory grade scale, the weights came out to:

283.42g
283.23g
283.25g
283.29g

Meaning either the coating is applied very uniformly, or I have mismatched piston weights and I fluked out getting the weights within 0.2g of each other. Gut feeling is that the coating is properly applied and its very uniform across the piston dome.

https://www.miataturbo.net/attachmen...ine=1391921877

Apparently a very dirty laboratory. :)

--Ian

Well they do testing for coal samples for the mining industry, this is one of their dirtier scales. It gets calibrated every year so I don't see that implies that it works any differently than a "clean" scale. ;)

I've used the Dart DC2 coating and it still remained perfect after 7k of serious abuse.

And as for the machining burrs - I've got 3 sets of Supertechs here and none of them look like yours.

Although I doubt this - but I'm curious as to weather or not they tried to clean out some of the coating that might have made it's way into places it shouldn't have been?

Bump from the dead,

I hate threads with "incomplete endings" so I'll try not to do the same here.

Everything has been buttoned up on the engine, been doing break-in for the past week or so. Unfortunately my oil pressure sensor kept leaking and I was pulling my hair out why, turns out BSPP threads need to bottom out to seal (doh!).

Did a bit of street tuning, so far I've pulled to 5000rpm. Still need to break it in a little longer to be safe before I raise the RPM limit. "Off" boost response is really good with the higher CR this year. I say "OFF" because I'm Rotrex'd and as such I'm boosting so long as I'm on throttle.

Hot oil pressure at idle is about 30psi, no piston slap during cold idle. Engine has a bit of a rumble to it now with the built head.

I'll be updating with some videos as it gets closer to dyno tune time.


FAB, if your last comment is related to the burrs there, they definitely weren't there as a result of any sort of "cleanup". The material looked the same as the base material of the underside of the pistons so its been fairly uniform. These are cheap pistons though so I'm not really complaining, just a little surprised something so basic would slip past QA/QC.

If that comment wasn't related to the burrs; I doubt they do any cleanup or need to. Looks like a fairly uniform masked line for where they've sprayed the ceramic coating on. Theres nothing in the path of of the rings or anything that would contact the cylinder walls.

Where did you get that supertech pistons smooth down?

What did you use for piston to wall clearance on your setup?

Using oil squirters or no?

Do you burn any oil? If so how much?

Sorry for so many questions, but I'm going to start my build soon and I'm trying to get as much info as possible to get it dialed in correctly.

The oil pressure sensor threads are bspt, not bspp. You have to use a sealant on the threads and the sensor should not bottom out.

Did you guys removed oil squirters or jets with coated pistons ? I'm thinking sending mine for coating too and getting rid of the squirters on the NB track car since the engine is in parts right now.

^^^ What are the benefits of removing the oil squirters?
Seems to me like you're eliminating some of the protective piston cooling by doing that.

Power and less cylinder wash. I don't need piston cooling on N/A track car. I think Bob removed them on his 300+ WHP turbo toy too...

Bob said his oil ran cooler without them. I say, of course it did. But the pistons are hotter because the oil isn't cooling them. If the oil was carrying the heat away from the pistons and out to the oil cooler, then the oil would be a little hotter.

The engine makes more power because the extra little bit of weight of oil on the underside of the pistons and being splattered on the cylinder walls creates a little bit more drag and resistance to movement.

Correct - I think a common misunderstanding is that most people think oil has one job, lubrication. It's actually responsible for +/- 40% of engine cooling.

Lubrication, cooling and cleaning. True race oil that's changed after every weekend doesn't include detergents so more of its volume can be used for the other two jobs.

As long as it doesn't get too hot, higher combustion temps will increase power. Doubt it's from oil weight on the bottom of the piston and "drag" from a slippery substance used for lubricant.

Crank scrapers make horsepower
by removing excess oil from the crank.

Different concept and only effective on motors where the crank counterweights touch the oil-unlike the BP.

For the burrs I used a a dremel tool and some sand paper, not much to it just making sure not to take off any excess material.

I am running 0.0023" PTW measured after coating, coating is at a maximum thickness of 0.0005"-0.001".

No oil burnt, car does not consume any oil.


I'm going to have to argue this one... The threads are definitely BSPP if you look at the OEM oil pressure sender the threads do not taper.

I have my oil squirters removed, the theory was that oil pressure should be more stable without them. This seems to be true so far with the datalogs from 3 track events so far.

If you look at the piston design, it does not utilize the oil squirters. Bob Bundy has a thread somewhere on here that discusses this. I actually took some photos of the OEM pistons which shows how the oil squirters work. Will need to dig around for them.

Less likely to do with "power and cylinder wash, more to do with "its not needed". As mentioned above the oil squirters do not work with Supertech's piston design.

Possibly true. Oil squirters would still spray oil in the general direction of the bottom of the piston, however with ceramic coating hard to say how effective this is as there is already a thermal resistance between the piston material and the area of combustion.

Raisin, I was actually talking about top of pistons. Around edge of the intake valves. Did you smooth them out yourself or did you get that done else where?

Are you planning on staying n/a?

No pressure lubricated automotive engines are designed to have the counterweights touch the oil in the sump. A Briggs and Stratton lawnmower engine is splash lubricated but that doesn't have an oil pump. The purpose of a crank scraper is to remove excess oil from the rotating crankshaft, both from the counterweights and the rod ends. Excess oil causes drag, increases rotating mass, and can disturb the balance of the engine.


What is a crank scraper

Nothing is touched except cleaning the burrs. Supertechs came and were shipped out as is to Calico shortly after.

To answer your question earlier that I missed: I'm not running oil squirters.

Car is currently running a Rotrex since day one.

Thanks for answering my questions, I'm starting a build soon and I just wanted to get info from people that already completed successful ones.

I was talking about this but supertech design must be different depending on the CR.
https://www.miataturbo.net/attachmen...s-piston-1-jpg

The pistons I'm using are the 10.6:1 option, part number P4-MA790-N1. They do have different dome designs based on the CR options.

That skinny sliver of metal is a potential hot spot and is ground down on factory pistons, and on my Supertechs by my engine builder.