Ceramic coating the heads, combustion chambers and exhaust ports but not the piston.. is it a good idea or it will overheat the pistons???

Since the heat will not go out through the heads into the cooling system it might get more heat to the pistons... Good idea or not?

This is something that was not covered on the other thread for ceramic coatings.

 

i dont think the differance will "make or break" a forged piston (assuming its a forged piston). It takes a good amount of heat to melt a piston or anything like that.

 

Any heat that you can keep in the chamber is going to produce more power. The piston will see about the same amount of heat, and the only way to melt the piston down is with a lean mixture or detontaion. Both of those will raise temps enough to melt the aluminum in the piston tops.

Keeping heat out of the coolant and in the chamber is good, it will allow the coolant to cool the hotter areas of the motor better.

One more point, the middle cylinders have a very hot spot between them, especially where the exhaust ports are. Now you can add some coolant lines to that area, or you can help the problem out by keeping the heat that causes that problem down.

Bret

 

Is it recommended?? heard that was not a good idea to deal with the combustion chambers in that way.. Let me know

Thanks

 

Why not coat the pistons also? Are you just installing heads on an already built shortblock? If you're gonna do one, might as well do it all. I think it will cause more heat build up in the piston.

 

Yeap.. the shortblock is in the car already with a set of AFR 190s and im upgrading.

 

My understanding (partially based on dyno tests by David Vizard) is that the one thing you do want to coat is the piston crowns. There is more power to be had there than with anything other single potential surface to coat. Those dyno tests show 4-6% peak hp increase as well as better WOT fuel economy, if I remember right.

Rich Krause

 

Thanks rich... You are a the master here

Im not going to coat the heads or anything really.. TEA talked me out of it...

but.... will let you know that I followed your advice, as always, and went with the 210 heads... I believe they are what I need...

Thanks!!! if you ever come down to PR let me know

 

This talk of piston coating has stirred up some interest in my head. When is it a good idea, I know you say that any engine can benefit from trapping all the heat possible into the CC, but is it just a waste of money on some engines.

For example a 381 with DP 300shot, all forged internals.

Also how expensive is it? What is a good coating? and who does it?

 

I have always gotten good service and results from Swain Technology at http://www.swaintech.com/race.html The thermal barrier coating (TBC) for the crowns is $24.50/piston. For a total of $32/piston you also get the skirts coated. I would do teh TBC for a 300hp nitrous shot.

Rich Krause

 

Is it a good idea to remove the headers and send them to swain tech? I have the headers coated by jet hot with its black coating on the outside and sort of white on the inside...

I would love to see someone that has coated the heads chime in.

 

Its on my list, for an extra $200 I figure it seems to be worth it, hell I got the pistons/rings for only $300 for srps brand new so might as well spend the difference to make them even better.

Are the power gains something that is noticeable, somebody said they looked at dyno results from coating pistons, you have a link or an email of the person that did these tests?
Edit: NM about that, just looked back over and saw the 4-6% peak increase, sounds worth it to me! Especially for the added safety, seems like a thermal barrier would make it safer for the pistons incase of detonation

 

I had my Pistons, Valves and Chambers Thermal coated for $530 and have not cranked up the boost yet, Still at 5psi, But I run on 91 octane and have run 32* Adv. @WOT with 9.6 :1 CR and have seen absolutley no detonation or KR. I am also running NPG+ waterless coolant so you get no boiling in the head passages as it pulls the heat out of the heads much better than coolant and water mix and doesn't boil until 375* . As far as I'm concerned any money spent to avoid detonation is worth it and I wanted a bullet proof motor.

 

A ceramic coating applied to the top of the piston will not protect it against detonation. The coating thickness is measured in microns (millionth of an inch), so it will have little effect against shock. However, coating the entire combustion area will prevent superheating, which leads to pre-ignition, which in turn can cause detonation (high-order burn rate).

A thermal barrier will not only keep heat from being leached away by the metal surfaces in the combustion area, it aid in heating the air/fuel mixture before ignition. That will promote a more complete burn which improves power, fuel economy and HC emissions. It may also deter the hot gases from reacting with the metal surfaces, which should reduce NOx emissions.

In addition to thermal barrier, ceramic coatings have also been formulated for heat dispersion, friction reduction and corrosion prevention. If you're the DIY type, or just can't afford commercially applied ceramic coatings, you may want to check out this company:

Techline Coatings

 

From the More Performance LS1 buildup article in GMHT
Like many parts in this motor special purpose coatings were applied wherever some advantages was seen. For the pisto ncrown a thermal barrier was used. This serves 2 purposes: first, it keeps the heat in the combustion chamber thus allowng a given amount of charge to generate a higher cylinder pressure. Second, it reduces tempatures seen at the ring belt and in the skirt area. Since the strength of aluminum drops off so uickly with rising temperatures, this move makes for a significantly stronger piston under operating conditions. A second type of coating is used on the skirt. This coating based on the super slippery compound PTFE, acts as a backup should the oil film fail. Because it acts as a sacrificial finish under emergency conditins, the piston can be run with closer clearences thus giving a small improvement in ring stability for a better seal.

The coating in the combustion chamber helps keep the heat of the combustion where it should be in the chamber. The coatings in the intake and exhaust play an interactive role. Because there is no water jacket between the intake and exhaust poet bowls, a great deal of heat is transfered through the aluminum wall separating the two ports. This causes the intake charge to heat up and the price paid for this is twofold. The heat not only reduces the air density, thus cutting the charge weight entering the cylinder, but also makes a hotter charge more prone to detonation. Isolating the heat of the exhaust from the head casting also lowers the demand on radiator area which if taked advantage of cuts aero drag on the car.

Wow that was alot of typing .