Coating piston tops with a ceramic coating

[keefallan]

I am getting ready to assemble my powerhead(115 crossflow). I am seriously thinking about spraying cerakote on the tops of the pistons and even the heads. I am unsure of the heads though. I am sure the piston tops will help. But I am afraid the head coating will make detonation a greater reality. I have searched numerous engine builder sites for more information. I am asking if anyone coated their combustion areas in their heads.......and did it help or hurt against detonation?

[FMP]

Know of a build that was done twice, both times coated crowns, possibility chambers too I'd have to check again. Melted them good both times, didn't listen to us telling him to use Wisecos.
Thought you weren't racing this build.

[keefallan]

I am not. I was just wanting to add protection to the build. I wasn't racing this last one either. But I was wide open when I threw a ring. And I was curious about the chamber being coated and did it help or hurt? I can see it doing both. But if someone had already done it.....then I would know for sure. I love to make things better.....sometimes overthinking it. I have pro v pistons with coated skirts. I f they weren't coated, you can be sure I would be bringing that up too.

[keefallan]

I do plan on using my hot heads again. But I know one will need replacing. I like the 20-25 boost in compression points. I don't wanna go back to 120 again. Hence my desire to protect my powerhead.

[FMP]

If you can maintain optimum temp in the chamber without excess heat sink in the head and piston and lose and use the heat out in the exhaust then it should be a positive.

[Chaz]

K Allen ,
I was going to wait until I got my parts back from the cryogenics guy to either post in the "merc rods" thread .. or just start a thread on the build of these two powerheads. I just really hate bogus info .. you know , i had a friend who .. Oh wait ..

Here it is straight ... I have been using header coatings for aprox 25 years.

I like yourself was leery of using any internal type coatings . At first , I tried just doing a set of skirts using Tech Line Coatings .. That was aprox 10 years ago .

https://techlinecoatings.com/

Sometime along the way , the company was bought out by a group of employee's . I was fortunate to get in touch with Jason at the Mfg. plant. He is well in tune with his product and one of the most savvy coating's people on the planet as far as I'm concerned .. ( right up there with Uncle Bud ) Actually it was Bud , who told me I didn't know what I was missing .. and turned me onto Tech Line ..

Skirts , yes ... underside and pin bores too .. NO MORE : scuffed skirts , oil coking under the crown or seized pins .

DFL-1 (dry film lube)



Piston tops , I was concerned .. that it might flake off , reflect to much heat away and not let the piston come up to temp and size . Or if the heads were done , that it would stop heat from getting to the water jacket and / or effect the reading by the cyl head temp sensor.

But first .. Wiseco's were mentioned , they have a hard anodized coating from the factory , that can be prepped and coated with a heat barrier as well .. or left alone , at least it's something ...



CBC-1

I took the plunge and did a set of tops. Just like any other "paint job" prep is everything. Alum oxide grit sprayed at 35 psi in the blast cabinet .. keep me greasy paws (rubber gloves) off the parts , slightly warm the parts in an oven to 85 - 90 degrees and spray a light even coat . When it dries , oven bake at 300* for an hour. i did an extra piston , smacked it with a hammer a few times .. no come off .
I've done about a half a dozen motors so far with the crown coating , no adverse effects .. !



Jason explained to me that the CBC-1 was a natural aluminum color .. and that some have been known to use it in class's where it is not legal .. (racers cheatin, who'd a thunk it )

I wanted to start using the gold color barrier like the T/F cars use , on both the piston tops and complete head surface . This is what he sent ..
After speaking with another bright young man the other night about keeping heat out of the intake tract .. I think I'll spray a couple set's of stripped reed blocks before I put them together ... Jr. your right , every little bit helps !



The next set waiting will be a pair of big inch motors. they will get the intake area , exhaust tract from port to tuner tip , water jackets , lower unit gears and shafts .. anything that makes heat or friction will be attended to ..



In the mean time , I'm pretty excited to get back the parts I sent out to chryo ..
Part of that batch will be two sets of rods that I , ground the beams, shot peened, bead blasted and coated . When they come back I will burnish in the bearing load area's , wash install new bolts and hang together ..

C-Lube ...






I'll send Jason a link to this thread as well ...

[keefallan]

If you can maintain optimum temp in the chamber without excess heat sink in the head and piston and lose and use the heat out in the exhaust then it should be a positive.

That was what I am wanting to do with it. Yes, my desire is to protect the combustion area. I also saw a test where a ceramic coated top basically removed all the heat from the underside of the piston........no heat transfer/absorbing. Thats the biggest reason why I wanted to do this. I saw it as a way of controlling the heat and trying to funnel it out the exhaust. Then I started thinking about the heads. Why not coat that area too? I liked that even more(top and bottom heat control)...........with the thought that I was forcing the explosive forces to do more work and a little less of the side effects of it...........heat/heat sink. But I was concerned about outboards being so sensitive to heat, that I couldnt get away with the head coating.

[keefallan]

Chaz, awesome layout of what you have done and are doing. It gives me the confidence to coat my heads. I was pretty much convinced about the tops of the pistons already.

I have too have been using exhaust coatings for a little bit......but not as long as you. Prep is definitely the most important part. Bad prep............stuff no stickey......or peel off at the worst time. I have been amazed at the quality of the rattle can coatings from vht. I have now used them on two sets of headers......properly prepped them........and applied the paint right.........they have not chipped or peeled. I was doing budget work , so I was giving it a shot. The truck headers have lasted for over a year now. I usually use a much better exhaust coating, but I can now attest that even the 7 dollar vht can will work and last if you do it right.

I am torn between using techline and cerakote. I remember when cerakote was available thru Jegs or Summit many years ago. Not anymore. You can buy thru them directly however. I did put in an application with techline for a business account. Their retail sales product line is a joke. I can only buy 3oz of cbc-1. I actually want to by the next grade up. So, I need them to approve my application, or will have to go to cerakote. I can buy larger quantities from them. I just want a quart.

I also found numerous sites that coat stuff for you. I dont have anything against the folks that you ship your stuff too. But, as far as I am concerned, its too simple a job to pay someone a huge amount of money to coat a piston top, when you can do the same thing with a touch-up gun and proper technique.

I think I will be coating my pistons for everything I build now.......be it small blocks or outboards. WHen I was researching for hours yesterday, I stumbled onto a test that Hotrod magazine had done on an engine coated and uncoated. They did the whole shebang on the internals...skirts, piston tops, oil shedding coatings etc. The motor gained 9hp. enough said.

Its like my friend back in the day, swapped out all his fluids in the motor and drivetrain to synthetics and picked up 2 tenths in the quarter.....free hp to be had.

These coatings wont ever make a cast piston a forged one. But it can surely improve on it.

Chaz, now you got me thinking about spraying the intake tracts and exhaust tracts of my crossflow stuff!!!!

[powerabout]

on a modded xflow I would add the finger ports.
that cools both the under side and the ears on the deflector

and yes i like with coatings, its the only thing that keeps the F1 car engines alive over several races.

[powerabout]

What does it do to the egt of the engine after coating?

[keefallan]

Hstream1, all of your work looks good. I really like how those pistons turned out............look amazing. I didnt post it earlier, but I was gonna blast my tuner and coat it as well........including the adapter.

I think I am gonna take lots of pics as I go on this build, post the build here.........to show what can be done. Hopefully it will bring more people to want to do this or get coaters such as yourself to do it for them.

I look at it like this. Synthetic oil is superior to crude. It always was. But it took many many years for people to see the light. I see internal coatings as the same thing. But then again, maybe its me who has been behind the times.......I dunno. If so, then I am getting up to speed. But its a win for everyone(to coat their engines internals). Theres some that can do it themselves and others who will want it done, and get others to do it for them. It makes the motor more efficient and last longer.......where's the downside?

Powerabout, I would love to see some diagrams for a fingerport or a boost port(best location in the inspection cover area and size) for a crossflow. I am not doing it on this one. This is just a runabout motor(that I am tweaking a little). I am doing my best to re-make a 140 get to the 140 power level. I know its gonna fall short a litttle. But I do expect it to give a mph or 2 better than my junk powerhead that I have on now.

[powerabout]

It usually alters the EGT readings and in all my experience youll need to richen up the Tune. Because the Coatings are doing exactly what they were designed to do. Burn Combustion efficiency.

I had two of my Coated motors at jasper last year that both placed 1st and 2nd in Pro Mod both days. We had to richen up the tune by 4%. Now alot comes into play. Adjusted Altitude, temperature, Humidity etc.

ok I wondered if the higher egt would be the new normal so the tune would be good?
Are you adding fuel to get the egt back to normal?

[keefallan]

Amazing. I appreciate you telling that.

[keefallan]

Yes But we've also found the motor is asking for more fuel because the combustion efficiency is increased.

So the motor is using the thermal dynamics of the combustion process to make more power instead of losing it into the surrounding metal as a "loss" or by-product?

[powerabout]

Yes But we've also found the motor is asking for more fuel because the combustion efficiency is increased.

not quite with you there, its asking for more fuel as it became more efficient?
did the bsfc go up or down?