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Garage => Mechanicals => Topic started by: raueda1 on 05 November 2019, 02:59 PM

Title: Ceramic coating exhaust manifolds
Post by: raueda1 on 05 November 2019, 02:59 PM
I'm considering getting exhaust manifolds ceramic coated. Then I learned that the coating will increase the emmisivity of the manifold vs uncoated cast iron.  Moreover, the color doesn't matter cause it's emitting infrared.  From a performance point of view if [coated]=[cooler exhaust] that's probably good.  However, the manifold is pretty close to various hoses and the engine compartment temperature is already high.  Anybody have any idea if the coated manifolds would materially raise it higher?  I'm probably overthinking things, as usual, but comments still welcome. 

And while we're at it, has anybody had custom, tuned headers made for a 6.9?  Anything to be gained?  Cheers,
Title: Re: Ceramic coating exhaust manifolds
Post by: daantjie on 05 November 2019, 06:20 PM
Dave, from memory there have been some posts on mods on the 6.9, notably this dude appears to have had some nice gains:

https://www.youtube.com/watch?v=BxN4AQNzFYE

However on the header front, I think success is limited due to extremely tight clearances, plus you are dealing with massive heat soak due to the engine bay being so tight.  Of course anything is possible with enough time and money, but I think it will still be marginal gain for the investment IMHO.

Title: Re: Ceramic coating exhaust manifolds
Post by: rumb on 05 November 2019, 07:52 PM
I used https://www.eastwood.com/eastwood-hi-temp-internal-exhaust-coating-w-nozzle.html on my 250S. I sprayed inside and outside. Has a nice silver color. I have no idea if it helps yet. I have had a real problem with vapor lock on that car and used the coating to try and help that situation.
On my 6.9 I sandblasted the exhaust and sprayed with clear VHT high temp paint. It turns them a nice grey color.
Title: Re: Ceramic coating exhaust manifolds
Post by: nathan on 10 November 2019, 09:07 AM
I had mine done on the 6.9 and the 280te im doing.
supposedly heat management is better, but im just tired of knowing they looked like crap.
I get them done a dark grey to look something like metal. I think originally they are light in colour but this would stain too easy (although the ceramic stuff supposedly cleans easier).
anyway, some pics on a thread from a couple of years ago
https://forum.w116.org/mechanicals/6-9-engine-rebuild-with-pics/75/

Title: Re: Ceramic coating exhaust manifolds
Post by: ptashek on 10 November 2019, 03:30 PM
I did mine in the 450SE. Can't say heat transfer changed in any way, as it's always, quite literally, hot as hell under the hood anyway ;)

They did look great for a few thousand miles, then went murky brown around the hotspots, and eventually the coating started cracking albeit it's not flaking off. That's about 15k miles after.
Title: Re: Ceramic coating exhaust manifolds
Post by: TJ 450 on 12 November 2019, 10:15 PM
Pretty sure it depends on who does it and the process. The ones on my 6.9 were done by the same mob as Nathan's and they're mint after quite a few thousand km.

Tim
Title: Re: Ceramic coating exhaust manifolds
Post by: oversize on 14 November 2019, 12:14 AM
I think there's definitely gains to be found with custom headers since the standard ones are very compromised with small collectors. Use the later tri ys as a basis for the design.
I would also add twin snorkels & cold air intake to get the most benefit.

Ceramic is the best option currently available ATM so just go with that but make sure they're thoroughly cleaned before coating.

I'd seriously consider bonnet vents to get rid of all that trapped heat....
Title: Re: Ceramic coating exhaust manifolds
Post by: floyd111 on 16 November 2019, 07:10 PM
Louvres on, or behind the fenders, like Buicks ;) Maybe with high power fans behind them.