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Discussion Starter · #1 ·
the internets said:
THE FACTS:

Header wraps are designed to keep the heat in the header to improve scavenging of the cylinders. Keeping the heat in the header allows the exhaust speed to remain high. (the right idea)
There are no header manufacturers that I know of that will warranty their headers if any header wraps are installed on their products.
In most cases the header wrap damages the headers beyond repair. (I will explain below)
If you run a lean mixture, you "may" see a slim performance gain using header wraps. A rich mixture may show slim to absolutely NO gain in performance.
If you do not mind replacing your headers and header gaskets regularly, and you like that ugly look of a wrapped header, go ahead and use the heat wrap.



BACKGROUND INFORMATION:

In the past, almost all NASCAR and other racing engine builders used the header wraps for the added power gains. But, after having to replace the headers after each race due to the wrap being about the only thing holding the header together, they do not promote the practice any longer! They now utilize the thermal coatings that are chemically and electrically applied to the headers. Those include Airborn, Jet Hot, HPC, and others.

Imagine having to replace a $1200.00 plus set of headers after each race weekend! Few but the most financially well-off race teams can afford to do this. But, it is also in the downtime for remaking a custom set of headers. Most custom header makers do not have copies readily available.

I believe that the wraps are good to protect various items from heat, but not to hold the heat in the header. For example: you can use the wrapping for the protection of fuel and oil lines, wiring, etc.

Cool air needs to be around the header, and insulating it with a wrap to hold exhaust heat in makes the header material temperatures near molten. When you wrap the header you trap the heat in the header, but also in the material that needs to breathe to dissipate heat for it's own survival.

Engineers, Metallurgists, and other experts out there will state that there is no way that the material can fail because it can withstand, and it was designed to withstand, the internal temperatures of exhaust gases. TRUE! But, when the header is not allowed to cool so as to dissipate those extreme temperatures that the wrap is controlling, you have now developed a heat absorption that compares to thermal friction which will will continue to gain in temperature beyond the normal exhaust gas temperatures (EGT's). This is the same as with most any insulation.

Try this experiment ... launder a load of bath towels and then dry them. Immediately pull them out of the dryer and just toss them in a snug pile on your bed. Now leave them there for a day and then open them. You will find that there is still a considerable amount of heat left in the center towels. This heat, even though the outer towels and bed are normal room temperature have been able to contain their heat. This is a simple thermal insulation test, but with your headers you have an internal heat supply coming from the engine. The heat on the outside portion of the header material is trapped between the warp and the header and will continue to fatigue the header. This build of heat is amplified by the wrap. Towels do not need to breathe, header material does.

The EGTs stay the same but the properties of the header material changes in a way of amplifying the temperatures because of the insulation. This action goes against normal laws of thermal dynamics, but this effect is fact, and you have to pull the ears off most engineers before they believe you. This is the trouble with plenty of education, but NO "common sense"!
http://www.centuryperformance.com/heatwraps.asp


Discuss.
 

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The internet is a big place with lots of opinions but without facts to back it up I cant give it much credence.

While it is true that header wraps can cause problems he completely missed the fact that it is usually due to the fact that as the header cool, water condenses on them and the wrap traps the water and corrodes the pipe. While this is less of a problem with stainless steel pipe it can still be a problem.

While the claim that it does not produce any horsepower gains seems a bit suspect since this person sells ceramic coated headers on his site. If he truly cared about his customers and even believed what he wrote he would be selling the cheaper headers that did not have the ceramic (heat retaining) coating

again... just my opinion... Like I said, the internet is full of them
 

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I agree with Brad about the condensation/rust. In general, hot exhaust gas = higher exhaust velocity = easier breathing = more power. Header wraps are one tool that may be employed to help keep exhaust gas temps high and insulate the heat from radiating to other components inside the engine compartment. It is possible that header wraps can trap too much heat allowing temperatures to rise above yield point thus significantly weakening the metal. Usually this only concerns people running very high output engines (more hp = more energy = more heat) or those with extremely tight engine bays. Properly applied ceramic coatings applied to both the inside and outside of the pipe help insulate the heat energy and do a pretty good job at corrosion protection. However, if just one part of the coating gets damaged that effected area will rust very quickly. Also, the coatings do sometimes fail (poor adhesion or other reasons) and break apart so you want to be careful about using them upstream of turbochargers.
 

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Lit like a BranchDavidian
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The proof is in the pudding.

I dont believe half the **** thats said. I have header wrap on my OBX header. The story about ASSCAR cars having chewed through a header in a race.... well remembber they are running at WOT a lot more and the temps are more extreme, so i call BS with that on a street car.

Like i said, i have had it on my cheap $170 header from ebay. It's been on for about 2 year and has seen MANY rainy days of driving and parking in the wet and about any other condition. But i am in Ga so im not exposed for the salt and sand of the northern state's winters.

But recently i had to take the wrap off to re-wrap them. Low and behold there was NO DAMAGE to the header after 2 years.

I believe what i see and i didnt see any cause for alarm.
 

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i think the real question is, do you care about performance enough to risk ruining your probably $300-400 headers with heat wrap. UNLESS they are the cheap OBX or other ebay brand then i say what the hell go for it.
 

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i think that more real world instances need to be found before we believe anything. i work at a MINI cooper dealer as a tech, and i can't tell you how many hypochondriac's walk through the door sweating bullets about something they read once on a forum. i try to triangulate, find three different instances that aren't connected, or try it yourself
 

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I've always heard wrapping a header will shorten its life. I don't doubt it. I wrapped by Racing Beat with it recently. I did it one because one I love the look, two I wanted to lower my under hood temp. Carbs love the cold air. It did help lower the temp under the hood a whole lot! I can actually put my hand on the header right after I drove it and not burn my hand. And it looks so sick! :)

It will probably go bad on me after 2 years. But hopefully by then I can afford a Maxim Work header or maybe I won't even have a Miata anymore.
 

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Lit like a BranchDavidian
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the easy to put wrap on is to soak it in water first.

I noticed DRAMATICALLY lower underhood temps. I'm sure its keeping a lot of heat out of the s/c that sits right above them.
 

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This information is interesting.

I have been debating installing header wrap on my Jackson Racing header.

Thanks for the info guys.
 

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If it's good enough for TODA it's good enough for little ol' me. My stock header is wrapped. Huge improvement in underhood temps.
-Ryan
 

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Dammit, Kyle!


That Toda pic!!

I just ruined another keyboard!!!
 

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Brah.
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got a quote from jet hot:


We'd charge $165 to coat your header in the 1300 Sterling finish. Add
$20 for the matte black, blue, grey or copper finish. The gloss black is
$50 additional and has an 1100ºF tolerance. We'll need them here for 5
days plus shipping time back. If the parts are chrome or nickel plated,
add $40 to the total and 2 days for stripping. Return shipping would be
about $34.

Technical benefits for the 1300 Sterling are as follows: Looks great,
reduces under-hood temperatures by 50 degrees Fahrenheit and more, keeps
pipes about 300ºF cooler, gives you 1-3% extra horsepower, extends
average header life by at least 10 times, and improves safety in an
accident by reducing the probability of fire-balling. It is also very
easy to keep clean. If you use one of the other 1300 colors, they
perform as well, but are not as cleanable. I will send you our full
information package to get you all the coating benefits in greater
detail.

If you upgrade to the EXTREME STERLING you get a coating that will stay
shiny 200ºF higher than Sterling, and take a maximum temperature of
1700ºF, though it does have an orange-peel texture compared to 1300
Sterling. It will also provide an estimated 100ºF more of insulation
and carries a 5 year warranty. It is recommended for low boost turbo and
supercharged vehicles, and lean running EFI cars. Cost is $50 more, and
takes an extra 2-3 days to process
 

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I have my P5's header wrapped for over a year now with no problems. It's my DD, so it's highway then stop and go around the city. I haven't had any issues with it. I'll probably wrap the headers for my roadster when I pick it up.
 

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here's a few things to consider.
1) headers(aftermarket) are not supplied with a HEATSHIELD! therefore, heat soaks into the engine. and the power adder" the header" actually becomes a power loser when heat builds into the engine bay.
2)exhaust manifolds (stock) are usually made of thicker...heavy-duty steel compared to the aftermarket mild steel materials,and are most all cases equipped with a heat shield. stock exhaust manifolds are not lighter... they are usually stronger to last the life of the car, unlike untried fancy materials like ceramic etc.

so are headers wrap still good?
yes!
its the application you use it in! it voids warranties because it can be used in the WRONG applications: if you have a ceramic coated header using mild steel...well you're screwed anyways of using this as a benefit. as the metal will give way by its increased heat scavaging and weak, light-weight metal. look, for those that like to counter my point... dare to use mild steel thats ceramic or whatever coat of your liking as your exhaust valves and survive that...and i'll send my apologies happily for giving a weak opinion. but stainless steel valves??? nah, that'll work. see any relations here?

o...remember, the heat isn't retained as its meant to be exhausted of course!!! so the towel example would be absolutely true if the exhaust gases had nowhere to go

since exhaust heat is contained in the manifold itself...more exhaust heat or newer exhaust heat are forced to be exited faster out the TAIL-PIPE. naturally, heat wants to expand and meet whereever its colder to equalize.

the question you gotta ask yourself is... when you replace an oem part with a "performance" part...are you not leaving anything else out that will keep it really performing? and did you study the product that you're dropping $$$ into to fit your needs of use.

just cover some bases is all i'm saying here.

people, look at your exhaust manifolds for a second...why is there a heat shield? and why is the stock manifold steel and not ceramic?

i'm not surprised the stainless OBX and headers wrap worked well. he left nothing missing on the mods. i dunno if he came up on this by accident or...?

not knocking on ceramic headers... but isn't it best used on cars that'll probably be auto-crossed? its light and cools quick for in-between runs and etc. but stays hot enough to function.

bottom line is, when you run aftermarket headers, you're turning your engine bay into the header wrap(but ib a bad way) if you don't have a heat shield.as excess heat from headers spill onto the engine and intake charge and...

wrap ANY headers(just not ceramic ones), i guarantee performance for your buck. its meant to be there just like the stock heat shield is meant to be there. hell...i felt more power from wrapping the stock exhaust manifold that had broken heat shield.

those of you out there running performance headers and are afraid of header wraps or are in doubt...just think about it for a second.
you got headers. they are bent differently for different power ranges, but they are not supplied with at least a cover for heat control. i'm no scientist...but the least amount of homework is at least find whats available to you to replace the stock heat control device you sacrificed...well, i wouldn't say sacrifice. cause these things perform a hell lot better.

well to those with ceramic mild steel headers... you either know exactly what you got it for or need to find other heat control methods.

thanks for reading my reply guys. i can't sleep, damn.

enjoy! now go buy some go*d&mn headers wrap!
ITS GOOD TO GO.
 
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