Jet Hot VS. Ceramic
 

O.K. Has anyone started a thread on "Jet Hot" verses "Ceramic Coatings". Which is better and Whats' the Cost.. I know I wanna do one or the other but really don't whats the differ-- Thanks

Jet Hot is a type of ceramic coating.

Mav

I can't speak about ceramic, but I just bought coated Kooks Headers from Maryland Speed. MS has an unbelievable price on Jet Hot right now. They sent my headers to Jet Hot for coating and JH shipped them to me. I am reposting these pics from another thread so you can see what Jet Hot's 1700* Extreme Silver looks like. The photos speak for themselves.

As for the price, I can't post that publicly, but you would do yourself a favor by calling Maryland Speed to get a real deal.

Obviously, I don't know how the coating will hold up after use, but check out JHs web site and see their excellent warranty.
http://www.jet-hot.com/

Alfie

Jet Hot is a brand of ceramic coating...probaly the best known brand. Same type word relationship as Xerox and copier or Tivo and DVR.

There are a lot of places that do ceramic coatings..all you really need is a paint sprayer, oven, and an in with one of places the manfacture the coating. That being said, most brand name coatings like Jet Hot or PM-FL are done on a higher level. The headers are cleaned when they come in, flow coated inside, and in the case of the silver coatings polished (which requires a pretty expensive machine). Not to mention coming with an actual warranty.

If the headers are stainless steel heat coating is a waste of money and in fact since SS changes shape as temp changes by heat coating then traps heat into the welded area and then welds can crack.
With cheap grades of SS used ( esp the junk many headers made in china or mexico) the pipe's expansion is different then the thicker welds and by trapping the heat with the coating will cause cracks.

SS transmits heat much better then mild steel so it does not need the heat coating which also can trap too much heat in the exhaust and effect the 02 sensors.

I knew I wasnt dreaming this. TY


its stainless Folks give ceramic coating time if you dont polish it then she will discolor , fog up and soon or later look like crap especially inbetween the primaries.

Like said above it is all pretty much the same, I use a Local Coating company Central CT coatings, Formerly Airborn Coatings to do all my Exhaust and Powder Coatings.

Cermic Metalic Coatings are For REAL, they work regarless of what material they are used on.

All of your Turbo Systems are made from stainless and we coat everything inside and out.

There are No Dangers with Proper exhaust coatings.

As far as Rust Protection goes it is affective but not perfect, the coatings are somewhat porus so moisture can get to the Steel Header Tubes and eventually start pitting with rust but is certainly makes Steel last a lot longer.

Ted.

Coating is a great product for vendors as there is a high profit margin in selling it but in fact use on stainless will change the velocity and cause welds to crack

What does happen is vendors wanting a larger profit margin use a cheap grade of SS and thus expansion at welds joints is even worse, trapping that heat into the welds by coating causes the SS to expand at a different rate.
If buying headers make sure it is made from a good quality SS and not the cheap junk sold by many makers of headers.

We have seen many SS headers with cracked welds due to coatings and those cracks causing air to enter into exhaust stream and effect the O2 output readings. Worse is one side leaking causing a AFR imbalance the PCM cannot adjust for.

Stainless steel is similar to mild and alloy steels; it is an alloy of iron that contains at least 12% chromium. This high chromium content retards corrosion giving the steel its "stainless" quality. There are many alloys of stainless steel, which are broken down into two basic categories:

Chromium-nickel grades
Straight chromium grades
The chromium-nickel grades are the more common stainless steels used in race car fabrication compared to the straight chromium types, due to the nickel content which provides excellent weldability and corrosion resistance. Also, this nickel improves some mechanical properties such as fatigue strength, toughness and ductility. People sometimes refer to stainless steels based on their chromium and nickel content: for instance, 18-8 stainless has 18% chromium and 8% nickel in it.

Stainless steel typically has a rather low carbon content, in the range of .08% to .15%, and sometimes as low as .03%. The carbon is needed for hardness, but it also can cause the stainless to become susceptible to corrosion at high temperatures. What happens is this: when chromium-nickel steel is heated to a temperature range of 800° to 1590°F, the carbon in the steel combines with chromium to form chromium carbides. This transformation is called carbide precipitation and reduces the corrosion resistance of the steel.

The chromium is reduced in this heat-affected area and makes the steel subject to what is known as intergranular corrosion. Some stainless steels are known as low carbon grades to minimize this carbide precipitation; others, such as 321, are special alloys that reduce carbide precipitation by combining and stabilizing the chromium at elevated temperatures.

People should know about maintaining high exhaust velocity and increase scavenging by covering headers with a thermal wrap. In addition, there are companies that coat headers with a thermal barrier, typically some type of ceramic formula, in order to keep the heat inside the exhaust system.

Stainless steel performs this function without the need for heat coating because it has a much lower coefficient of thermal conductivity, thereby keeping more heat inside and transmitting it to the header outlet rather then radiating outside.

Radiated heat is perhaps the most important reason to wrap or ceramic coat mild steel headers to protect the car and the driver from excessive, fatiguing high temperatures.

Typical 1010 carbon (mild) steel conducts 219% more heat per foot than do the types of stainless steel we use in header fabrication. By contrast, quite a bit more heat stays inside the stainless header tubes and does not get passed into the surrounding air. By not allowing the contraction of the cooling gases as they flow down the tubes, more exhaust velocity is retained which promotes better scavenging at the collector. This retention of velocity increases the overall header efficiency.

You've probably seen Indy cars with their enclosed engine compartments and thermal clam-shell enclosures around their turbocharger headers. They must thermally wrap their exhaust pipes just so the radiant heat off the tubes won't cause fires or melt any critical systems.

In this case headers made out of mild steel would completely fail and break apart due to the severe heat retention, let alone scale and send death particles into the turbocharger, ruining the turbine blades. 321 stainless steel has excellent high temperature fatigue resistance in this enclosed application and does a darn good job of living in this hostile environment better than any other material except the ultra-high nickel content steels ( such an Inconel ), which are hard to find, very difficult to work with and extremely expensive.

These many characteristics, such as superior heat retention properties, high temperature fatigue resistance, and to a lesser extent, the cosmetic value of a non-rusting finish, combine to make stainless steel an ideal choice for headers and exhaust systems. Such a system will produce more horsepower and last "'til the cows come home". It is an excellent solution. Now that you are sold on the merits of stainless steel, there are a number of things you need to know about the different types available before you launch into a header and exhaust system project.

A three-digit numerical classification system is used throughout the industry. The racer needs to be familiar with only one of these three-digit series within the system - the 300 series. They offer the fabricator a wide array of choices, from ornamental quality up through the highest-temperature and closest-tolerance aircraft quality.

Within the 300 series of stainless steels, there are four types that are suitable, available and cost effective for the racer. These are 304, 316L, 321, and 347.

321 and 347 are known as stabilized grades of stainless. These are alloyed with either titanium (321) or columbium (347), both of which have a much stronger affinity for carbon than does chromium at elevated temperatures. This eliminates carbide precipitation leaving the chromium where it belongs for corrosion protection...remember our discussion of intergranular corrosion? Both 321 and 347 are top choices for exhaust headers, especially turbocharger systems and rotary engines. Since 321 is much more available than 347, that leaves 321 as the first choice, with no sacrifice in needed qualities.

316L is an extra low carbon (ELC) grade of stainless that has only .03% carbon, making less carbon available to precipitate with the chromium. It is used extensively in marine exhausts where salt water corrosion mixed with diesel exhaust particulates and electrolysis create such a horrible environment that even other grades of stainless cower and run away!

304 is the most inexpensive and available stainless in the 300 series. It is suitable for normally-aspirated header applications, and has been successfully used by many racing teams. It does not have the high temperature fatigue resistance that 321 does, but is considerably less costly and much more available. Most 304 tubing these days has the dual designation of 304/304L.

Practically speaking, there are overlapping applications of 304 and 321 stainless in header construction, but knowing you've got the insurance of the aircraft-grade 321 for the job is definitely worth consideration of the extra cost... if your application requires it.

Stainless steels come in both tubing and pipe sizes. Since certain pipe sizes are almost identical in dimension to tubing sizes, pipe may sometimes be substituted for tubing, and vice versa. Numerous wall thicknesses are available, but for headers, normally .049" (18-gauge) to .065" (16-gauge) is used.

Different specifications are used to meet particular requirements for the military (MIL), the American Society of Testing Materials (ASTM), and the Society of Automotive Engineers (SAE). Examples of what to look for when you order stainless tubing are as follows:

ASTM A-554 304 stainless is a welded mechanical tubing used primarily for ornamental purposes. It is not fully annealed and is work-hardened slightly in manufacturing. It has good column strength and good bendability.

ASTM A-269 304 stainless is a general service commercial specification that is higher quality and is fully annealed for better ductility. It is available in both welded seam and seamless, and is a good spec for the racer to use. We have not seen any difference in longevity between welded seam and seamless stainless tubing in header use, but there is a substantial cost difference. The column strength is not as good as A-554, but it has excellent bendability with a higher cost due to the full annealing.

MIL-T-8808/8606\MIL-T-6737 321 stainless are military specifications for aircraft tubing. Suffice it to say that some MIL-specs are not necessarily better or even as good as some ASTM standards. There is no particular magic here.

I really don't want to get in an agrument. In terms of the material data, you are correct in the differences between the grades. That is almost manufactuer sized knowlege. However there are some parts that are wrong. First off, I have sold well over 1000 Jet Hot coated headers, and have never had a warranty claim for a cracked header. It just DOES NOT happen. This is slelling Kooks, SLP, SW, and so forth. Header wrap does crack headers, and most manufactuers will not warranty a wrapped header. They will however warranty a coated header, and in some cases even offer coated headers themselves.

Here is good reading on that issue-
http://www.centuryperformance.com/ex...e-spg-138.html

As for profit margin..we normally sell coating at cost. The funny thing is..most places don't like dealing with coating because it is hard to make money on, and more of a hassle with shipping the header around, and having the customer asking when their header will be done. It's easier to sell an uncoated header and be done with it than deal with coating.

On the tuning end of it, the coating keeps more heat inside the header, which presurizes it more and increases exhaust velocity. The faster air leaves the engine, the quicker a new A/F charge can replace it. It basically helps your header breathe easier, and be more efficiant. I have seen some tuners complain "Well a coated header does not take as much timing without detonating". They are not accounting for the fact that you advance timing to fix an inefficiancy. Because coating makes your engine breathe more efficiantly it does not need as much timing. It short a coated header can make the same power with less timing because of increased flow efficiancy.

As for how well coating works at cooling on a stainless header...I can drive my car with coated headers for an hour..come home and park it, and within 20 minutes, the header is cool enough to touch (I am not recommending trying this yourself). That does not happen with an uncoated stainless header or stock manifolds.

JR-Vette, :facepalm:

You going to add a link to that Copyright © 2004 Burns Stainless LLC All Rights Reserved tech article from Burns Stainless?

Or you trying to play that off as your words with the top paragraph of snide remarks toward the reputable vendors on this site added?

:paddle:

Hahahah busted! :paddle: I was just about to google a line from his post because I just KNEW he lifted that from somewhere. :D

SLP headers come stock with polished aluminum ceramic coating inside and out.

FACT
stainless steal wants to retain it's original shape - flat
It changes shape as it heats up, the welds to it do not.
You cannot expect the pipe itself is thin and brackets or collectors are thicker that they react the same to heat and expansion.

the proof of what happens when heat coating is used and the damage to the headers and the engine is common, just a few

http://www.teamzr1.com/ubbthreads/ub...=3251#Post3251

Vendors selling headers where their costs are less then $300 and then selling them for $1200-$1600 claim they have never seen problems, the car owners with blown heads have

The fact with engine management and feedback sensors leaks in headers cause untold damage as the 02 sensors only know what the 02 content is and PCM is making false adjustments so when head ends up too lean, the other way lean and a total imbalance to fuel trims.

There is zero reason to coat stainless steel, if heat is a issue entering the car then a heat mat can be used.

Most tuners and almost all car owners do not know if weld cracks, some are so thin the only way you see the problem is to use a smoker and in custom tuning for 15 years I have seen countless tunes that were screwed up because the tuner was masking the problem which is to make the side leaking richer which forces the PCM to make the other head way too rich.

If anyone thinks those big buck headers they have that were built in Mexico or China on $5 a day labor is high quality I suggest as a minimum is use a good OBD scanner and see if the short, long term fuel trims, fuel injector pulse width and 02 outputs are equal left/right.

Else I can show images of burned pistons and valves all due to header leaks causing lousy AFR to cylinders.

They need it to protect the headers from surface rust. 409 grade stainless...