Header ceramic coating color

[lippy]

I'm planning on having my sidepipes ceramic coated in black. I also will have the headers ceramic coated, but am deciding if they should be black, or another color. I don't think it matters if I have the headers one color and the pipes another because the collectors will cover the headers on the outside of the car so the headers won't be visible from the exterior.

For the headers, what color is most effective from a heat perspective (does it even matter much)? What color looks best under the hood?

[bobcowan]

For the performance factor, it won't matter. They will all perform about the same. As for color, that's strictly up to you. I prefer black, but they all look good, IMO.

[DanEC]

I don't off hand know the answer to your specific question. But, if your goal is to keep underhood temperatures down, coating both exterior and interior of the headers will definately help with that.

[patrickt]

I was going to have my primaries ceramic coated black, and Peter specifically warned against it. He said they just wouldn't hold up as well and I would not be pleased. So, I followed his advice and went with the silver color which, apparently, wears much better. And now, in hindsight, I think the look of silver is better as well.

[lippy]

Originally Posted by patrickt

I was going to have my primaries ceramic coated black, and Peter specifically warned against it. He said they just wouldn't hold up as well and I would not be pleased. So, I followed his advice and went with the silver color which, apparently, wears much better. And now, in hindsight, I think the look of silver is better as well.

The reason Peter said that is because his supplier only coats in silver. If you want black, he coats in silver and applies VHT paint over the silver. The guy I'm using can coat in silver or black with equal durability. I think any ceramic coating will lower temp, and it mainly comes down to looks for me.

Do you have silver primaries and black sidepipes? If so, can you see the transition from the outside of the car?

[patrickt]

Originally Posted by lippy

Do you have silver primaries and black sidepipes? If so, can you see the transition from the outside of the car?

Yes I do. You can not see the silver primaries from outside the car. You can not see the transition from the primaries to the side pipes from looking down in the engine bay unless you strain to do so. The only time you will ever see the transition from the primaries to the side pipes is when the car is up on a lift, you're under the car, and you are looking here:

[lippy]

Originally Posted by patrickt

Yes I do. You can not see the silver primaries from outside the car. You can not see the transition from the primaries to the side pipes from looking down in the engine bay unless you strain to do so. The only time you will ever see the transition from the primaries to the side pipes is when the car is up on a lift, you're under the car, and you are looking here:

Thanks, that's really helpful. Exactly what I was looking for. I think it probably looks pretty cool to have silver primaries and black sidepipes.

[patrickt]

Originally Posted by lippy

Thanks, that's really helpful. Exactly what I was looking for. I think it probably looks pretty cool to have silver primaries and black sidepipes.

Maybe someone else will post some pics of black primaries; I don't have any. But here is a shot of what you see when you look down at your primaries -- you don't see all that much. So, the choice between black and silver is purely one of personal preference. In hindsight, I would not change.

[tkb289]

--- Which color is most effective … The shop doing the coating should be able to answer that one, or their supplier. The differences are most likely negligible.

--- Which color looks better … Now that's a bit more complicated. It comes down to what 'look' you are after and what you like. Best to think of it in terms of the whole motor, just to name some of the choices:

- What color block?
- Cast or stamped valve covers, painted or polished?
- Style and type of air cleaner?
- Color of distributor cap and wires?
- Polished or natural finish intake manifold or alternator?
- V belt or modern serpentine belt?

Take a look at Cobra Country, as there will be at least one motor photo with each ad. That might give you some ideas.

The list of choices and decisions just goes on and on, which is all part of the fun!

[DanEC]

I can shoot a picture of my black coated headers this evening. In general the black tends to fade a little more into the general darkness along the lower sides of the engine. The bright sliver ceramic coating would provide more of a contrast in the engine bay.

[patrickt]

From Rick Parker's gallery -- it gives you an idea of what black primaries look like:

[olddog]

In terms of performance, it is best to not let the exhaust gasses cool, because pipe velocity drops when the gasses cool. Black absorbs heat. Shiny, reflective surfaces reject heat. Therefore a silver coating on the inside of the pipes would be better than black, from a performance perspective.

Although this is true, I wouldn't expect a huge power difference. A race team, looking for every last pony, may do this if the rules allow. Maybe someone has ran a dyno with and without coated pipes and can speak to the difference.

I'm not saying this is going to matter, however silver is theoretically a step in the right direction.

[DanEC]

Lippy - not the best of pictures but you can see that in the crowded engine bay, black makes the pipes essentially disappear. If you want them to stand out then a silver ceramic would be better.

[AL427SBF]

olddog -
Black absorbs heat. Shiny, reflective surfaces reject heat. Therefore a silver coating on the inside of the pipes would be better than black, from a performance perspective.

We all know that applies if the heat you are absorbing or reflecting is from a radiant glowing object (light source), not so sure you can apply that same logic to hot spent gases pumped into a pipe. The ceramic coating with the best insulation properties is best, and I think color has no bearing on it - it's just dye in the ceramic mix. I'm no expert that's for sure, just my opinion.

[Gaz64]

Originally Posted by AL427SBF

olddog -
Black absorbs heat. Shiny, reflective surfaces reject heat. Therefore a silver coating on the inside of the pipes would be better than black, from a performance perspective.

One of oldest arguments in the automotive world.

Black or silver radiators come to mind.

[olddog]

Originally Posted by AL427SBF

olddog -
Black absorbs heat. Shiny, reflective surfaces reject heat. Therefore a silver coating on the inside of the pipes would be better than black, from a performance perspective.

We all know that applies if the heat you are absorbing or reflecting is from a radiant glowing object (light source), not so sure you can apply that same logic to hot spent gases pumped into a pipe. The ceramic coating with the best insulation properties is best, and I think color has no bearing on it - it's just dye in the ceramic mix. I'm no expert that's for sure, just my opinion.

I have worked in process control 35 yrs., and I have actually tested temp readings with air and polymers. Believe me radiant or infra red temp transfer happens everywhere all the time. It will affect the exhaust gas temp, but how much that will impact Hp is another question.

[Skuzzy]

I think a lot of the confusion about the color and how it handles heat is due to how we know color works.

Black does not reflect any of the *visible* light spectrum. Which is to say it absorbs all the visible wavelengths in the light spectrum. That is the key. Both UV and IR are not visible to the human eye. This allows for some "blacks" to actually reflect those wave lengths and not absorb them.

At that point it becomes less about the color and more about the material the color is made of and/or the material the color is covering.

Just my two cents.

[lippy]

Black absorbs and radiates best. Since the headers won't be absorbing that much radiant heat, I think black would be preferable. Theoretically. But I don't think it makes much difference in practice. I'm leaning toward a matte silver for the headers because I think it will look good against the aluminum engine.