headers - ceramic coat or not?

[Oz66FB]

Hi guys
apologies if this has been posted before.

I have seen plenty of "tech notes" from exhaust manufacturers suggesting ceramic coating is the way to go.

can anyone speak from experience or provide an independant point of view?

Do they perform better?
Do they reduce engine bay temps?
Do they last longer?

appreciate your opinions
cheers
Ben

 

[Rusty67]

Hi guys
apologies if this has been posted before.

I have seen plenty of "tech notes" from exhaust manufacturers suggesting ceramic coating is the way to go.

can anyone speak from experience or provide an independant point of view?

Do they perform better?
Do they reduce engine bay temps?
Do they last longer?

appreciate your opinions
cheers
Ben

I can definately say it helps to lower the engine bay temps somewhat. As far as lasting longer I have heard it both ways. No one I know has given any difinative evidence either way. As far as performance, I don't really know for sure.

 

[Stanger007]

Go with a quality ceramic or JetHot coated.

I made the mistake of not getting either on my longtubes. The heat that they throw off is MUCH greater than the same set of headers on my buddy's car.

I have a pair of JetHot coated ones in the shop waiting to install now... learned my lesson.

Wes

 

[danny clemens]

This is just an opinion but I would say that they would help make a little more power. The reason I say this is they keep underhood temps cooler and when your engine takes in cooler air it makes more power. That is if it has an under hood air filter opening.

 

[BullittStangV8]

I have my Hooker super comp ceramic coated, and they have not discolored or worn out at all. very nice pieces.

 

[65fastbackresto]

My Patriot Try-Ys look good too

Ceramic looks good, a buddy of mine has a car worth at least twice as much as mine, its NICE. But when you open his hood and see the cooked painted headers its a big disapointment considering how nice the car is.

 

[69gmachine]

They last a lot longer. They're supposed to make more power by keeping the exhaust temps up, which keeps the velocity up near the head. I have no way to prove that one way or the other, but it definitely keeps engine bay temps down.

 

[ratio411]

Snake oil.
They are just looking to add an option to their retail product.

Headers actually wick heat from the engine when uncoated and that is part of the overall good they do for not only HP and TQ, but economy and engine temps as well.
If the heat is in your engine bay, then it is not in your engine.
One reason to get headers is to let the engine itself run cooler than cast manifolds.

Word of warning, if you decide you just must have coating, ask the header company you choose if their headers are coating inside and out, or just outside.

Hooker, for example, only coats the outside.
I have seen forum posts where Hookers have rotted from the inside out because of this.
I find it strange, but I guess the super heated interior of the coated headers does it.
I have had uncoated headers last for decades.

Jet Hot is a Hooker header dealer.
They buy the headers wholesale uncoated, then coat them inside AND OUT.
Usually for the same money or less than Hookers coated by Hooker on the outside.
Just a heads up.
If you are going to buy snake oil, you might as well get the best snake oil out there.
Dave

 

[ratio411]

This is just an opinion but I would say that they would help make a little more power. The reason I say this is they keep underhood temps cooler and when your engine takes in cooler air it makes more power. That is if it has an under hood air filter opening.

That is what hood scoops are for.

The engine runs better if it expells heat, as opposed to holding it in.
In a perfect world, heat is energy, however the level of technology (and fuel) we use for the internal combustion engine cannot turn excess heat into energy.
Therefore it must be expelled quickly and effieciently.

This allows us to run the maximum level of compression, amount of timing, and quality of fuel possible, with the available metalurgy and cooling systems.

A tiny bit of extra port velocity at the head is not worth holding in enough heat to possibly cause detonation, reduce available ignition timing, tax the cooling system, etc...
That said, I admit these problems would be most apparent in an aggressive engine that is running on the edge of streetable, but that is what alot of us do strive for...

 

[68keyblr]

If nothing else, they look great and stay looking great for a long time. I'm thrilled with my summit racing coated shorties.

 

[zookeeper]

If uncoated headers last for decades, coated headers must last for centuries! Really though, I've had my last pair of uncoated headers, nothing looks worse than rusty headers and there's no such thing as good header paint, so it's either rust or coating, take your choice.

 

[ratio411]

If uncoated headers last for decades, coated headers must last for centuries! Really though, I've had my last pair of uncoated headers, nothing looks worse than rusty headers and there's no such thing as good header paint, so it's either rust or coating, take your choice.

I wasn't joking.
Me and my old man put headers in his Chevy in 78.
They are still there.
The car hasn't been out much in the last 10 years, but before that it was daily use status.

You gotta do header paint right for it to last.
The factory doesn't do it right.
The paint that comes on them is considered there for "shelf life" only.
The header companies will tell you that too, if you bother ask.

 

[zookeeper]

I wasn't joking, either. There is no such thing as good quality header paint. I've been trying various paints and methods since around '76, and I've never, ever had good luck, nor have I seen anyone who's had header paint last more than a few weeks. By the paint lasting, I mean look as good as the day it was sprayed, not that there were flakes of paint between the rust. I know lots of guys like to think that their way is the right way, and if you've got a method that works for you, dandy. But I'm pretty picky about how my engine looks, and you'll never see rusty headers on my cars again.

 

[69gmachine]

That is what hood scoops are for.

The engine runs better if it expells heat, as opposed to holding it in.
In a perfect world, heat is energy, however the level of technology (and fuel) we use for the internal combustion engine cannot turn excess heat into energy.
Therefore it must be expelled quickly and effieciently.

This allows us to run the maximum level of compression, amount of timing, and quality of fuel possible, with the available metalurgy and cooling systems.

A tiny bit of extra port velocity at the head is not worth holding in enough heat to possibly cause detonation, reduce available ignition timing, tax the cooling system, etc...
That said, I admit these problems would be most apparent in an aggressive engine that is running on the edge of streetable, but that is what alot of us do strive for...

Ratio, what I want to know is what kind of weed are you smokin' man??

 

[ratio411]

Ratio, what I want to know is what kind of weed are you smokin' man??

 

[Oz66FB]

wow guys thanks for the responses. i have been travelling for work so first time i have had a chance to get back on here.

it seems the consensus is looks and under hood temps win. Performance gains are questionable. the engine is race only so looks are not so important but power and torque gains are.

I have only found one independant article and it actually shows power and torque drops with the ceramic coating but outside temp of the headers is 50% less.

http://www.carcraft.com/techarticles/high_tech_ceramic_coatings/index.html

It also suggests that they have to be coated inside and out for max benefit.

One thing i was wondering is if the heat is all retained in the header, will that make mufflers and the rest of the exhaust burn out quicker?

thanks again for all the responses
Ben

 

[Rusty67]

Yes, because the exhaust will not lose as much heat in the header, it will disapate farther down in the exhaust system. If you have cats to worry about it is a much greater issue. It might also wear out mufflers sooner if you don't have cats.

 

[ratio411]

Mufflers with fiber packing will suffer from more heat in the exhaust.
Chambered mufflers without any insulation won't care one way or the other.

Any muffler should be placed as far back in the system as physically possible for 2 reasons.
1: Hot exhaust gasses displace more area, therefore your exhaust flows less the hotter the gasses. A muffler that gets exhaust that has had a chance to cool and shrink, will flow more than a muffler that gets hot gasses.
If you think about it, the muffler is the one biggest exhaust restriction in the whole system. If it can be made to flow better, then the whole system (and power) will benefit.

2: Mufflers with any packing, insulation, fibers, etc... last longer when cooler.

In theory, if you coat the headers, you need to upsize your exhaust to flow better.
That means adding weight, bulk, and using larger diameter stuff.
If you don't coat the headers, you have to believe that smaller pipes (therefore lighter and less expensive) will flow better due to the shrunken displacement of exhaust gasses.

On that note, IMO, any supposed gains from keeping heat in the exhuast are nullified by adding weight and expense to keep the same flow rate.
Remember that weight lost is effectively power gain.
Much the same as mandrel bent pipe vs non-mandrel.
A 2.5" mandrel pipe, for example, flows more exhaust than non-mandrel 3" pipe.

 

[blandq]

I've run both taped headers (I'll never do that again as long as I live) and ceramic coated (yes inside and out) And regardless of how long they last, less heat is radiated into the engine compartment than straight steel headers. Though I can't quantize the benefit, I have seen it. With wrapped headers my electric fan came on almost immediately when stopped at a light in the summer. With the coated headers I lasted noteably longer prior to fan coming on. Since in both cases the car IS NOT moving and the chassis/hood/engine mods, etc. remained constant between the two, I can only assume that more heat went out the tail pipe than was radiated into the engine compartment.....Did not need or care about longevity at that point, just keeping the aluminum cooler was good enough for me.

 

[4MuscleMachines]

I like to buy them uncoated then trial fit them onto the car. This way you can massage them to fit if necessary and then send them to JetHot for the coating.