Author Topic: Ceramic Coating - saving old mufflers  (Read 4719 times)

canuck750

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Ceramic Coating - saving old mufflers
« on: February 12, 2015, 08:35:35 PM »
I had a pair of very rough V7 Sport Silentium shark gill mufflers, most of the chrome peeling off, pits, rust. It took a lot of sanding to get the chrome off, right down to the copper under layer and sanding out all the rust and pits. The local powder coating pros coated them twice with sanding in between.

I think the results are amazing.

Before



After










crc

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Re: Ceramic Coating - saving old mufflers
« Reply #1 on: February 12, 2015, 09:34:09 PM »
well done jim ;-T

canuck750

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Re: Ceramic Coating - saving old mufflers
« Reply #2 on: February 12, 2015, 09:52:23 PM »
well done jim ;-T

Thanks!

The 750S3 I bought suffered a brutal maiming, the shark gills were cut off to make the ends of the mufflers blunt, probably looked a little more modern some 32+ years ago. The previous owner babied the S3 for the 32 years he was its guardian, I was told the original owner chose to cut off the gills. I know shark fins are taken for ancient medicinal purposes, who would have though the gills would be in equal demand.




Offline rodekyll

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Re: Ceramic Coating - saving old mufflers
« Reply #3 on: February 12, 2015, 10:49:14 PM »
That looks very good.  Do the rest of the system and the radiating temperature will go way down.  I went the same route with some old pipes some years back.  I was told that ceramic coating the pipes inside and out was a good way to hold heat inside and hopefully stop baking my feet and legs.  I never even think about getting dry-scalded by my exhaust anymore until these topics come up.   


Mine have taken a baked-on tannish patina from years of running hard in mud for days and putting it away wet, but the ceramic has held up pretty well.





I ride the same roads you do, so I think you'll be pleased with the coating and bemused by the color change.


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Re: Ceramic Coating - saving old mufflers
« Reply #3 on: February 12, 2015, 10:49:14 PM »

Offline Phang

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Re: Ceramic Coating - saving old mufflers
« Reply #4 on: February 13, 2015, 12:10:54 AM »
I know shark fins are taken for ancient medicinal purposes, who would have though the gills would be in equal demand.


Oh yes, we add dried gills in the soup to enhance the taste but usually taken from smaller fish  ;D

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Online Petrus Rocks

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Re: Ceramic Coating - saving old mufflers
« Reply #5 on: February 13, 2015, 07:07:08 AM »
My shop sandblasted the chrome and coated my pipes for my Triumph.  They look great and are much cooler to the touch.

bpreynolds

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Re: Ceramic Coating - saving old mufflers
« Reply #6 on: February 13, 2015, 07:20:27 AM »
Nice job.   ;-T

Hey lemme ask a question as per ceramic coating.  I bought my '99 Tbird a couple months back, thing is in pieces in my garage as I attempt to rejet/rebuild carbs, change cams, and airbox mod.  A previous owner had the header pipes coated as you can see.  On some bikes - like the op's ride here - I think the coating looks brilliant, but some reason I'm up and down about them on my T-bird.  I have read that ceramic coating headers/pipes yields less friction and some small - maybe miniscule? - performance gain and then on a few other and much more rare sites I've read they may negatively affect fueling.  I can't imagine why the coating would specifically and negatively affect fueling other than any modification to exhaust usually requires some carb tuning and that's to be expected.  Anyhow, what do you guys know?

« Last Edit: February 13, 2015, 07:26:22 AM by bpreynolds »

Offline Two Checks

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Re: Ceramic Coating - saving old mufflers
« Reply #7 on: February 13, 2015, 08:46:07 AM »
A 99 model car wth a carb?

A friend just put a stroker engine in his truck and had the headers ceramic coated by of all outfits, Kodak. Yes, that Kodak. And they sure are purdy.
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Offline Triple Jim

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Re: Ceramic Coating - saving old mufflers
« Reply #8 on: February 13, 2015, 08:51:07 AM »
I have read that ceramic coating headers/pipes yields less friction and some small - maybe miniscule? - performance gain and then on a few other and much more rare sites I've read they may negatively affect fueling.  I can't imagine why the coating would specifically and negatively affect fueling other than any modification to exhaust usually requires some carb tuning and that's to be expected.  Anyhow, what do you guys know?

If an exhaust system is tuned in a beneficial way, and you change its temperature significantly, like by adding or removing insulating wrap, the speed of sound changes, and the tuning changes.  The speed of sound increases with temperature, so the pipe effectively becomes shorter as it gets hotter.

With thin coatings, the change in temperature of the gas is not as great as with a thicker insulation.  Measuring the exhaust gas temperature before and after applying the coating would be a reasonable way to find out if there was a significant change, as opposed to reading advertizing literature.  Generally, coatings of a few thousandths of an inch of thickness don't do much to heat transfer, since convection at the gas-surface interface is a bigger determining factor than the conductivity of the coating.  

Emissivity on the inside surface will probably end up being determined by the sooty film that develops, but going from a polished chrome outer surface to a black surface on the outside could make a measurable difference in pipe temperature.  What appears to be black to the infrared frequencies of a hot pipe might not be what our eyes perceive as black though, so it's possible that hot pink could have an emissivity the same or higher than black, for example.

The cute and handy IR thermometers that you point at a surface and read its temperature assume the emissivity is near 1, so if you want a fairly accurate reading on a chrome exhaust pipe, you need to do something like spray some black exhaust paint on a spot on the pipe, take the measurement, and then remove the paint with solvent later.
« Last Edit: February 13, 2015, 08:53:44 AM by Triple Jim »
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Offline Cam3512

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Re: Ceramic Coating - saving old mufflers
« Reply #9 on: February 13, 2015, 12:45:25 PM »
Appropriate time for this post.  The pipes look great Jim.

It's motivated me to have the headers and crossover on my V7 Special ceramic coated black.

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Offline steamdriven NZ

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Re: Ceramic Coating - saving old mufflers
« Reply #10 on: February 13, 2015, 12:57:33 PM »
Hot Rod Magazine have a side issue called Engine Masters. They did before and after dyno testing of an engine before and after ceramic coating of the headers they had fitted to see if increased power claims were real.
The ceramic coating provided NO performance increase, but it did provide a remarkable reduction in radiated heat from the pipes. This would be quite useful for reducing underhood temps, so if the headers on my 73 C10 come off for any reason I'll get them ceramic coated.
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Offline Cam3512

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Re: Ceramic Coating - saving old mufflers
« Reply #11 on: February 13, 2015, 03:40:16 PM »
http://www.gsdcoatings.com/cmsms/index.php?page=exhaust

This is the place I've used before in New Jersey.  They also have a "chrome" ceramic coating that looks damn close to the real deal.
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canuck750

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Re: Ceramic Coating - saving old mufflers
« Reply #12 on: February 13, 2015, 03:57:58 PM »
http://www.gsdcoatings.com/cmsms/index.php?page=exhaust

This is the place I've used before in New Jersey.  They also have a "chrome" ceramic coating that looks damn close to the real deal.

Agreed, the 'chrome' is pretty darn impressive, the shop I go to has large drum polishers full of ceramic beads, they take large parts like car exhaust headers and tumble polish the ceramic coating. Lacks the 'blue' of nickel show chrome but it's still a very good option, and it will outlast chrome.

As a comparison to get the original Silentium shark gills chrome plated was going to run me around $800.00, the ceramic satin black cost $200.00. Since I am using these black pipes on a 750S3 it's a perfect fit.

 


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