Coated headers
 

I like this....http://forums.pelicanparts.com/uploa...1303869062.jpg
http://forums.pelicanparts.com/uploa...1303869083.jpg
http://forums.pelicanparts.com/uploa...1303869103.jpg

That looks like aluminized coating ? My boat headers were done like that back in the late 70's. Where is that getting done & expensive ?

It is ceramic. Swain coatings, not too expensive, I haven't seen the final price but under $300

nice.

Looks great post final product for us.

Is it durable (will not crack if it got banged / dropped) ??

Baked on at 3000 degrees. supposed to be really durable.

what problem does it solve for $300?

The idea for crowded engine compartments with V8s is to reduce underhood temperatures for cars with cooling issues (my old 74 corvette..it worked on the track) and supposedly create less local heat for crammed engines....especially when one builds equal length headers that take up more space and cook spark plug leads and accessories (AC cobra, MB 450 SLC 5.0).

I don't know what it does for 911s other than esthetics, perhaps others have some insight.

This physical principle applies: Heat goes from a hotter area to a cooler area. If you notice, the heat exchangers on a 911 run next to the engine. Exhaust system temp. next to the lower valve cover measured at 400ºF. Ceramic coating should reduce this significantly.

Were the interior walls of the exh. tubing also coated? If so, that might actually mummify (preserve) the entire exh. system.

Sherwood

I understand the concept (and am not criticizing) but I wonder how much of a difference it actually makes for a 911 at speed with cool air flowing over the headers all day long. Are engine temps really that much lower? Does it negate having as much oil cooling (that would be great)? Did the factory use it? Do current vintage racers use it? Do you need the inner walls coated too?

It would have more benefit on a turbocharged engine. More heat (energy) stays in the exhaust gas flow, increasing velocity and meaning more energy to be recaptured by the turbine, and so quicker spool, too.

Cool air or not running under the vehicle, heat radiates from the exhaust pipes onto the surrounding area.

Thermax temp. sensor on exhaust valve cover. About 260ºF:
http://forums.pelicanparts.com/uploa...1303885632.jpg

CU:
http://forums.pelicanparts.com/uploa...1303885505.jpg

If exh. temp. is reduced, the temperature in this area will also be reduced. Does it register on the oil temp. gauge? No or hardly. Consider the engine cooling system has add'l cooling capacity - i.e. more headroom.

Ceramic coating is a relatively recent technology. The factory used heat shields in selected engines. Here's an example on a GT2 engine. I would imagine modern race engines use titanium or inconel exhaust tubing for this purpose:
http://forums.pelicanparts.com/uploa...1303886005.jpg

Sherwood

I live in Alabama. I don't care how fast you are going, the air is thick enough to slice in the summer. I want this engine to run cool, (3.6) and last a long time. This is my plan. Plus, it looks fantastic and 100x better than those rusty headers. I looked with the light in the header and they did a pretty good job coating in the inside.

They claim 30 to 50% reduction in heat. We will see. I have had cooling issues with this motor even with additional cooler and duct cut in the tub. The rest of the exhaust is jet hot coated. The heads and pistons are being coated too plus bigger valves.

I'll be interested in your info/impression of any advantages to coating the heads (combustion chambers ?), since I had a bunch of coatings done to my engine (2.7L), which I will be eventually installing it in my car. I had the piston tops, combustion chambers, valve faces< & exhaust ports coated. Plus, I also have a set of coated headers to use. I had a lot of stuff dry film lubricant coated also and wonder if that might help with cooling somewhat.

Coating technolgy will give you a few bhp. Coatings will also increase component longevity. I'm working on a new column for Vintage Motorsport magazine. The more I learn the more I'm impressed. NASCAR is the leader in this area. That's why we're getting so many F1 guys working in North Carolina. Concorde is the place to learn about cutting edge coatings.

Richard Newton
'73 911

Marv, I haven't run anything yet as the heads and pistons are just getting sent off. My machine shop guy, who builds a lot of drag motors and roundy round motors, said he is not too sure on the bearing coatings but feels that the anti friction coatings on the pistons are very good. The head coatings are not that much compared to what the head work is going to cost. I figure that this will be a good test mule for some other motors that I am working on.

Swain is probably the best coating company on the market. Sure you don't all that shiny cool looking coatings that the other companies have, but what you get is something that works. I have a DP coated with it and after I run the car I can literally touch the pipe with out melting my skin to the exhaust. Pretty cool stuff, no pun intended. ;)

I had my heat exchangers and muffler aluminum sprayed 20+ years ago. NO rust yet on the muffler, the heat exchangers are starting to show a couple of rust spots.
Cost was ~$300 at the time. Way cheaper than stainless. So for corrosion resistance it's cost effective.