Coating for Headers
12-09-2006, 01:27 PM
#1
1st Gear Member
Thread Starter
Join Date: Jul 2006
Posts: 142
Coating for Headers
I thought that coating is good to prevent rust/corrosion and keep temperatures down. However, I recently was told that it is NOT necessary for SS304 grade which is impervious to rust/corrosion and has a low thermal conductivity. Coating is recommended for non SS or SS409 grade headers. Also, I was informed that the coatings only typically last 2-3 years, afterwhich they start to chip off? If this is the case, then why do some SS304 grade headers (i.e. Kooks, MAC, etc...) offer the option of coating?
12-09-2006, 01:58 PM
#2
RE: Coating for Headers
From what i have read and heard, having any type of header coated is a good idea. Firstly the stainless steel headers will discolor after some use, and the ceramic coating supposedly keeps the headers looking good. Secondly most headers will eventually rust even if it is only surface rust. I read a thread on another site about Some JBAs. They were stainless steel and they rusted. I don't know what type of S/Steel but they rusted. The ceramic coating also keeps down heat inside the engine compartment and helps with exhuast scavenging. It probably does chip after a couple years. IMHO it would be good to get a ceramic coating on any type of header no matter what type of steel it is made of. Thats just my $.02 about it though.
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[IMG]local://upfiles/42298/1D2DAA4A123C410294088069BBD0EE19.jpg[/IMG]
12-10-2006, 07:38 AM
#3
3rd Gear Member
Join Date: Aug 2005
Location: New Braunfels, TX
Posts: 882
RE: Coating for Headers
ORIGINAL: jmart69x
If this is the case, then why do some SS304 grade headers (i.e. Kooks, MAC, etc...) offer the option of coating?
If this is the case, then why do some SS304 grade headers (i.e. Kooks, MAC, etc...) offer the option of coating?
12-10-2006, 12:01 PM
#4
5th Gear Member
Join Date: Mar 2006
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Posts: 2,544
RE: Coating for Headers
ORIGINAL: scramblr
Probably for the same reason the stealerships charge ~$200 for scotchguarding the interior...easy profits.
ORIGINAL: jmart69x
If this is the case, then why do some SS304 grade headers (i.e. Kooks, MAC, etc...) offer the option of coating?
If this is the case, then why do some SS304 grade headers (i.e. Kooks, MAC, etc...) offer the option of coating?
EXACTLY.
By the way adj86, the JBAs you mentioned rust becasue they are 409 stainless. 304 and 409 are totally different.
12-10-2006, 01:36 PM
#5
RE: Coating for Headers
By the way adj86, the JBAs you mentioned rust becasue they are 409 stainless. 304 and 409 are totally different.
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Thanks for the correction CrazyAl. What are the main differences between the two?
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Thanks for the correction CrazyAl. What are the main differences between the two?
12-10-2006, 01:49 PM
#6
5th Gear Member
Join Date: Mar 2006
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Posts: 2,544
RE: Coating for Headers
Stainless steel is a steel alloy that has Chrominum added to it to improve rust resistance and to reduce corrosion. However, there are many different kinds. In the USA we identify the different alloys by a number.
409 is the cheapest type of stainless. It consists of Iron, carbon, and chromium. Some people call it "a mixture of plain steel and stainless" becasue it can and does rust, just not as bad as ordinary steel.
304 stainless consists of iron, carbon, chromium, and also has Nickel added. It has far superior rust and chemical resistance to 409, but the addition of Nickel makes it more expensive. It also has lower thermal conductivity than 409. That's good for headers becasue it helps trap the heat inside the header (like the thermal coating does).
You can read more here: http://en.wikipedia.org/wiki/Stainless_steel
409 is the cheapest type of stainless. It consists of Iron, carbon, and chromium. Some people call it "a mixture of plain steel and stainless" becasue it can and does rust, just not as bad as ordinary steel.
304 stainless consists of iron, carbon, chromium, and also has Nickel added. It has far superior rust and chemical resistance to 409, but the addition of Nickel makes it more expensive. It also has lower thermal conductivity than 409. That's good for headers becasue it helps trap the heat inside the header (like the thermal coating does).
You can read more here: http://en.wikipedia.org/wiki/Stainless_steel
12-10-2006, 03:05 PM
#7
3rd Gear Member
Join Date: Sep 2006
Location:
Posts: 853
RE: Coating for Headers
Coatings have a place, but are not needed on a 304 ss Long tube header.. Also the Ceramic Coatings that look like chrome, actually change color also.
Coatings chip and flake off. So that is another issue.
The Coating can hold so much heat inside the primary near the exhaust port that the combustion chamber can heat up and lead to lower timings being needed.
(Also the exhaust valves are hotter when this happens)
Now when I do go turboed. I will have all my pipes coated even when they are 304 ss, because with a turbo you not only want to keep it hot but the temps get crazy. People even wrap the ceramic coated pipes still.
I'm actually thinking of wrapping the first primary in each header about 10 inchs with exhaust wrap just to lower the radiant heat a little more, since the first pipe is almost the length of the engine before it drops down.
Coatings chip and flake off. So that is another issue.
The Coating can hold so much heat inside the primary near the exhaust port that the combustion chamber can heat up and lead to lower timings being needed.
(Also the exhaust valves are hotter when this happens)
Now when I do go turboed. I will have all my pipes coated even when they are 304 ss, because with a turbo you not only want to keep it hot but the temps get crazy. People even wrap the ceramic coated pipes still.
I'm actually thinking of wrapping the first primary in each header about 10 inchs with exhaust wrap just to lower the radiant heat a little more, since the first pipe is almost the length of the engine before it drops down.
12-11-2006, 12:34 AM
#8
RE: Coating for Headers
Thanks for that article CrazyAl, i now know the difference between the two types of stainless steel. As far as coating goes, I suppose that i would probably error on the side of caution and still get them coated. Mac makes stainless steel LTs, but why are they $469.00?
12-12-2006, 05:15 PM
#10
2nd Gear Member
Join Date: Sep 2006
Location: Erlanger, KY
Posts: 273
RE: Coating for Headers
If you want a good header coating, check out this link...these guys claim they are the original and they warranty their work against rust through and if you have any problems period in three years, they will fix it. http://www.nitroplate.com/index.cfm