Header temperature verses Downpipe temperature

[agteacher]

Need advice/input on the downpipe temperature verses the headers temperature.

We are going to get our Downpipe coated at Jet-Hot coating but, we are not sure of the MAX temperature the downpipe will reach.
We have a EGT gauge on the headers (bung is 6inches below the turbo) and the Max temperature of 1625 degree on a run—before we had the 2000 degree coating on the headers.
Jet-Hot said their Extreme Silver coating is good to 1700 degree BUT the silver coating will dull and may bluster. 1400 degree is a SAFE MAX degree and they will guarantee for life at this max degree.
We have Extreme Gray 2000 degree on the headers but we were looking for a little bling on the downpipe.

Thanks for the Help

 

[turbofabricator]

Need advice/input on the downpipe temperature verses the headers temperature.

We are going to get our Downpipe coated at Jet-Hot coating but, we are not sure of the MAX temperature the downpipe will reach.
We have a EGT gauge on the headers (bung is 6inches below the turbo) and the Max temperature of 1625 degree on a run—before we had the 2000 degree coating on the headers.
Jet-Hot said their Extreme Silver coating is good to 1700 degree BUT the silver coating will dull and may bluster. 1400 degree is a SAFE MAX degree and they will guarantee for life at this max degree.
We have Extreme Gray 2000 degree on the headers but we were looking for a little bling on the downpipe.

Thanks for the Help

Buy a stainless down pipe and polish it. Then polish it again, then again and then again, every time it goes dull. Thermal coating a mild steel down pipe looks pretty good, but if BLING is your thing, (geeze, I'm a poet and don't know it!) polished 304 stainless or better yet 321 stainless is the way to go.

 

[rmar]

Turbofabman is right.
I do coating for a living. And the polished is work. But worth it.
but for bling you will only be happy for a little while.
If you coat it. I'm using my 87 GN right now as a
lab rat with some ceramic coated bling on the turbo exhaust housing and dp and exhaust manifolds.

Most of the high end materials with any bling factor
will turn at about 13 to 1400 f. metal temp 1500-1600 egt
Survival rate 0/none/nil/nadda/.
I put a thermal barrier down first and then coated with the ceramic bling. AFR

 

[TurboDave]

I don't know much about bling, and coatings and all that stuff, but I can address your temp differential question. As general rule of thumb, you can expect a 200° to 400°+ temperature drop across the turbine housing. It will vary widely depending on a lot of factors, like load, rpm, etc.

 

[DCVING 6]

For what it's worth, I had my headers and DP ceramic coated. I don't remember the exact temp rating, but the guy said it would work even on a turbo'd car.
Well the headers have pretty muchly completely faded out, but the downpipe still looks good. :redface:

 

[scot w.]

I had mine polished and like it alot!

 

[rmar]

DCVING6 what color or material was the ceramic coating
you had done.

Thanks

 

[DCVING 6]

DCVING6 what color or material was the ceramic coating
you had done.

Thanks

It was done at LoKo in Alsip, IL... SERVICES LO-KO™ Perfomance Coatings, Inc.

 

[agteacher]

Thanks for the info

1st. the bling was an “after-thought” for ME on the downpipe (my students like bling…bling ).

2nd the MAJOR concern is the coating durability and if the coating will reduce the under hood temperature and STILL retain it’s luster/shine. Also, will this reduction in temperature improve performance and drivability?

This is an experiment: we are going to remover the EGT probe from the header bung and attach it to the downpipe (at the bend –after the turbo) with a 3” SS hose clamp. This will put the EGT probe next to the metal on the downpipe and give a reading of the temperature that the coating will be seeing. We will also wrap the probe/downpipe with thermal barrier wrap to keep temperature constant.

Are we on the “right track” with this intent of recording the temperature of the downpipe???

THANKS again....for all the HELP

 

[rmar]

Go to Tech Line Coatings.com
I've tried alot of stuff out there, this is about the best. But I guess that
is just my opinion. A lot of these materials you can do yourself.
Some are better than others some will fade some will not.

In powder/thermal/ whatever it seems like the better looking a material is the less functional it is.