Ceramic Coating?

[OLJustice]

Stainless still headers are always cheaper than ceramic. Does anyone know the benefit of cermaic coating of headers? How long will they last without coating? Also, does blue-ish or bronze discoloration of pipes mean they are no longer good?

All I can see that ceramic coating does is prevent this discoloration. Can headers actually "go bad"?

[Super T]

Ceramic keeps the heat in the header, that's all (but this is a good thing, keeps engine bay temps lower, keeps exhaust moving faster).

If the headers aren't stainless, they'll rust out. Not worth buying if they're not stainless. When they are stainless, the bluing of the pipes is normal, it's from the heat (I think it's the vanadium in the stainless that turns blue, but I don't remember for sure). They'll last about forever either way.

[OLJustice]

So the bluish discoloration is normal? Good, I was concerned. I've seen bronze (the stock midpipes are nearly brown), but never blue. Also, is there a noticeable performance loss due to just using Stainless Steel headers instead of coated?


Thx for the quick response btw

[grinner]

dont worry about the rainbowing colors. To me, the ceramic coating was an aesthetic mod to keep em all chromey. I know it keeps things cooler down the pipe but that aint why I did it.
You will have some that argue that the ceramic coating constricts flow a bit. I cannot argue against this as, mathmaticly, the pipes are now smaller in diameter on the inside, microscopic as that may be.
bottom line... if you wanna do it for performance, I'd skip it.

[Super T]

If you keep the heat in the pipes and out of the engine bay, then the exhaust stays hotter. Hotter gas is less dense... or, "bigger." Therefore it has to move faster through the pipe... the cooler it gets the more it slows down. The theory is that the faster it stays, the better power you can make.

[stroguy]

That is the theory and Jet-Hot has tested with and without their coatings. With gets some hp and exhaust gas speed increases.

If you keep the heat in the pipes and out of the engine bay, then the exhaust stays hotter. Hotter gas is less dense... or, "bigger." Therefore it has to move faster through the pipe... the cooler it gets the more it slows down. The theory is that the faster it stays, the better power you can make.

[OLJustice]

Hmm.. the question is, what type of HP gains? I mean I'm not gonna pay an additional $249 to coat these things if all I'm getting is +5 HP. My concern is price vs performance, and additionally, whether or not I'm doing any potential damage to my engine bay by not coating them. Anyone running non-coated LTs that can help me out? If the blue-gold rainbow coloring is just aesthetic then I couldn't care less, no1 sees 'em anyway.

[stroguy]

If you were willing to pay $200+ for the intake (AFE II) for a minimal hp gain then the expense of having them coated seems justified. Contact Jet-Hot and they will quote you a price and send a ton of information with tests.

I am in no way affiliated with Jet-Hot. I did the quote thing on some JBA shorties and was impressed at the information they sent me.

[mr.niftie]

Grinner,
What you lose ever so slightly in i.d. you gain more back from the smoothness it adds bettering air flow.

Also,
We all know about heat soak and how it should be avoided as much as possible, it is truly amazing how much a set of coated headers will lower the underhood temps!

[Armor-Clad Ind.]

A lot of good information has been put forward in this thread. I don't know how much I can add, but I'll try.

The ID change is approx 1 mil (.025 mm or 1 thousandth of an inch); so nominal loss of the ID is maybe 1.5 tp 2 mil. You ain't gonna notice that...ever. The 5+ HP (and that is highlydebatable) you will likely notice and your track times will reflect.

Some people apply a OD ceramic coating as well. This is principally for corrosion and asthetics. There is some thermal barrior, but the ID coating is more critical in that respect. If you coat ID and OD, then you never have to worry about corrosion and you'll get the HP gain (as already mentioned) through a greater scavenging effect. No more need for brittle stainless steel to merely get corrosion resistance! Anyone here ever see a cracked header flange on stainless (likely lots of people raising their hands at home)? This is the inevitable result of that color change on your pipes. That is a 'heat-affected zone" (welding term). Multiply that numerous times over and you have work-hardened metal which eventually fails. On the other hand, cheaper (but better metalurgically speaking) steel pipes coated with high temp ceramic give you rust "proofing" rather than the rust "resistance" of stainless. Basically, the only reason to (ever) use stainless is for the corrosion resistance. Now, thankfully, that is a thing of the past.

The $249? Not bad given that you'll gain power and fuel economy as well as have headers so rust resistant you could pee on 'em...if you were so inclined.

There are other benefits but I am tired, hungry and cold, so I got's to go.

Dr. B, NIC Certified applicator
Armor-Clad Industries, LLC
www.armorcladindustries.com
(website is not up yet, but will be soon...like in a week or so. And,yes, we do coat headers!)

[Armor-Clad Ind.]

I quoted a job recently and the guy responded, "I can get headers coated for $200." I was surprised as that is really cheap. He gave me the company's web address and I saw immediately why it was so cheap. He had been getting his customers' headers coated on the exterior only. Somehow people have begun thinking that this is the best method for performance gains and that is simply not true. It's either that or builders are lying to their customers. The exterior high temp coatings are generally applied thinner than the interior coatings and they do not have as much thermal barrier properties as the internal coatings for several reasons, not just the thickness issue. Just a little FYI so you guys can make more informed decisions, regardless of who coats your parts.

I haven't even started talking about the other stuff yet, like forced induction coatings...

Dr. B

[crhemi]

Can a used set be coated?

[gooeytek]

you can coat used headers.

I had stock SRT8 manifolds sent to Jet-Hot, instead of going the JBA shorty route, and still came out ahead. It came out to about $230 for Jet-Hot (they coat them inside and out) and $100 for the manifolds. Lower underhood temps are a good thing.

uncoated:


coated:

[MikeEast]

That's an AMAZING difference - like jewelery!

Mike

[duce]

get them coated. even stainless WILL RUST. the coating will not only keep heat out of your engine bay but will also thin out the exhaust causing it to move faster and will help protect them from rusting! All stainles will rust in time some just take longer than others.