Ceramic Coating

[subsonic]

I see Andrews point.  Keeping the intake tract cool.  Not coating it would be kind of like blowing your cooled charge through a heated pipe right before it goes into the combustion chamber.  I mean Daves high speed intake manifold is ceramic coated inside and out.

[JetPo]

So the question is : Is the price of coating worth the extra power ?

[subsonic]

Well, if you just ceramic coated the pistons, and did not do any skirt coatings, it would be about 100 bucks.  What else could you do for 100 bucks?  Rebuild a set of injectors if you have your own pop tester.  That would give you a good gain.  Perhaps run a cold air intake pipe.  I think the pistons would provide the best bang for your buck.  Even heat distribution accross the piston crown, less heat soak into the piston.  Less heat into the oil from the pistons.  The ability to run up to higher operating temps for periods of time with out damaging the piston.  Slightly better efficency with heat means more for work, ie turbo spool.

I guess in the 100 dollar range, I think it is the best application of funds for the payback.

[LeonardoL]

Check out this very long but very interesting article:

http://www.patentstorm.us/patents/5915351-description.html

Gentleman,

I think tylernt has brought an interesting point here, and probably the reason why coating the pre-chamber itself is a really bad idea.

By 935racer experiment and the patent description above, we have theorical and empirical evidence that the coating should go between the surfaces of the pre-chamber that exchange heat with the air and the head itself.

The surfaces of the pre-chamber can be viewed like the regenerator from the Stirling engines, keeping part of the heat for the next cycle: they should store a good amount of heat and deliver it as fast as possible for the next cycle, for good efficiency of the whole combustion process.

I never saw the pre-chamber and don't know if a coating like that is possible, but I see that as a way to reduce losses and really improve efficiency.

Cheers,
Leonardo

[NintendoKD]

I actually didn't read all of the way through this.  I am very interested in the engineering aspect of this as I would like to manufacture precups from ceramic.  Here is my take, a vortex is created by combining slow moving low pressure hot air with fast moving high pressure cold air.  The two push against each other and move up and around, at the exact same time they attempt to equalize each other passively "movement from one concentration to another"  I don't understand how exactly the inderect injection process takes place from injection to combustion "kind of a black box of unknown for me"  Hot air comes in injection occurs in a cone like shape, now the air is heated via compression and then cooled by the cooler fuel being injected and the two begin their dance, the air cools more rapidly as the fuel heats up and atomizes and expands into a vapor, the temperature equalizes somwhat between the air and fuel, thermodynamically speaking it happens slowly but to us this is a rapid process.  The air fuel mixture from the beginning is doomed somewhat because of the cooling process of the aluminum head and components rapidly absorbing and transporting the heat away.  someone once explained to me that the hot air moves quickly and the exhaust gasses move slowly and this is a trait unique to indirect injection.  Please correct me if I'm wrong, I also plan to get my engine coated and running a low static comp.

thanks,

Kevin

[smutts]

Wow! This be a right rave from the grave, I wondered what happened to this one!

I was suprised that the ceramic coating of the alloy cylinder head in the prechambers didn't seem to help efficiency/ power. Didn't some of the japanese idi motors used ceramics for the precups instead of iconel?  How well do these magic coatings adhere to the engine components? 

[jack's lack]

If you are intercooled, then increased boost does not increase heat.  Quite the reverse.  Increased boost reduces temps.  Increased fuel to air increases heat.

Andrew

what i meant was, coat the pistons/combustion chambers so i can run alot of fuel and alot of boost and keep the temps high inside the chamber with the boost/fuel but not have the side effect of toasting a piston due to the fact i have an NA block with no oil squirters

and im talking about running non-intercooled to keep combustion temps higher and more efficient... 25PSI should be about 170 degrees on a .60 t3 compressor

Maybe off topic, but what about the turbo? Sure the coated pistons will be less likely to melt, but the turbine isn't going to be any happier about being 1500ºF is it? I aways thought the concern about EGTs was primarily for fear of melting the turbo.

I know people have ceramic coated their exhaust manifolds, turbine housings, and downpipes, GeeBee has probably done his entire exhaust, but at some point we approach diminishing returns right?

I just did my piston domes, but I did not run the engine before I did this so I have no control to verify against to determine what kind of gains it produced in terms of power or efficiency.

[GEE-BEE]

I did the exhaust manifold, Both turbo housings & Downpipe on my AAZ

I learned from the thermal protection on my Ti exhaust on my 997TT and my Ti exhaust on my Desmosedici

The TI headers on my Porsche still look great and you can shut down the motor and touch the exhaust and headers after a minute or so..

Lucky I have a buddy with a powder coating shop that also does ceramic, he just adds my stuff to whatever he is running that day..

My wrench goes crazy when he see's my S/S metric or TI hardware for my installs,it seems I powdercoat everything I take off before I reinstall.

Latest was my axle and leaf spring's and followed with S/S U-Bolts for the spring's and new Poly spring inserts and S/S brake lines.

Gee-Bee