FYI: Exhaust radiant heat

[G3i Ignition]

Yesterday doing a dyno run @ G3i facility on a new concept exhaust system for ?Vetterman Exhaust Systems?. At 100% power the pipes started to turn cherry red @ 1300f and lean for peak power 1440f bright red/orange. Should of flip the lights off for moment, would have been a good pic. We took a few pics of it for the curious. The example shown is to make aware of the radiant temps that are inside the cowl and components are subjected to. That?s all?.Go Bronco?s

[rocketbob]

It would be really interesting to see what happens to CHTs if one has the insides/outsides ceramic coated.

Easier said than done on used pipes.

Its nearly unheard of in the racing world to run uncoated pipes.

[Veetail88]

Just a curious thought as I have absolutely no prior knowledge, but wouldn't air moving through the engine compartment keep those pipes quite a bit cooler?

It seems that in a test cell you likely don't have that kind of airflow over them. ??????

[bkthomps]

Originally Posted by rocketbob

It would be really interesting to see what happens to CHTs if one has the insides/outsides ceramic coated.

Easier said than done on used pipes.

Its nearly unheard of in the racing world to run uncoated pipes.

even on air cooled engines?

[Doug Rohrer]

Aircraft glow underlighting!

[hohocc]

On the Vetterman exhaust website there is a paragraph under FAQ entitled "How about ceramic coatings", implying they keep heat in the head. No numbers quoted though.

[BillL]

When I ran a dyno in the lab, one day my cell neighbor (common control room between cells) was running maximum power at peak torque ( diesel past regulated fuel) and it was about 1400F for a while getting the data point. I know it was not true, but I swear it looked like you could see the turbine wheel turning through the housing.

Neat stuff, and reminds us why we have shielding FWF for critical things that don't like to be hot.

Thanks for sharing!!

[Toobuilder]

Originally Posted by BillL

?... I know it was not true, but I swear it looked like you could see the turbine wheel turning through the housing....

Yep, we used to see that with the mighty J-58 too...

[Charles in SC]

I used to have occasion to fly a Piper Navajo. A section of the exhaust was visible through a vent on the side of the cowling. After dark this would glow pretty good even at altitude in cold temps. I do not know if it was any special metal or not. I think some of the Cessna twins had their pipes made out of iconell or something special to stand the heat but I do not remember hearing that about the Pipers. There is a lot of heat there for sure!

[Gisnar]

Do not want to hijack this thread (if this question needs to be moved great!).
But, what has been the experience with ceramic coatings and wrapping the exhaust on our little piston engines?