Any negative effect from heat taping headers?

[GaryR]

This would be on an air cooled 911 with SS headers. The positives are less heat transfer to the engine but will holding the heat on the SS instead of letting them cool in the open air negatively impact the steel or even the exhaust ports of the heads? Just curious, haven't seen any 911's done but it's common on other race cars.

Posted in the 911 Tech Forum also, not sure how much crossover there is..

[HawgRyder]

It would depend on the version of stainless that is used in the headers.
304 is the bottom end of stainless....308 and 316 are better quality, but I don't know if they are less prone to cracking than the 304 stuff.
My first question would be...is there a strain on the welds?
If the headers were "forced" into position for welding, then the heating/cooling would eventually break the weld.
Good quality (not cheap Chinese) units will last for centuries.
Bob

[K24madness]

With all of the modern ceramic coatings available wrapping becomes less appealing. Wrapping traps water and smells funky when wet.

[Tippy]

If anything from my basic knowledge of metals, the wrap should slow the cooling down which actually extends life of metals.

[MBruns]

We have seen mild steel headers turn to dust pretty quick due to retaining so much heat, and moisture. SS will tolerate it better, but will still be effected, all things being equal SS headers do retain heat better than mild steel , because of that we see a little better power numbers, on a 911 engine with them being underneath I would not wrap them, either coat them or SS

Mike Bruns

[Flieger]

Inconel+ceramic!

[euro911sc]

Originally Posted by Flieger

Inconel+ceramic! == $$$$$$$$

There I fixed your post

-Michael

[Flieger]

Yes, but they would be nice.

[efhughes3]

Originally Posted by HawgRyder

It would depend on the version of stainless that is used in the headers.
304 is the bottom end of stainless....308 and 316 are better quality, but I don't know if they are less prone to cracking than the 304 stuff.
My first question would be...is there a strain on the welds?
If the headers were "forced" into position for welding, then the heating/cooling would eventually break the weld.
Good quality (not cheap Chinese) units will last for centuries.
Bob

304 is far from the bottom end of SS. 400 series comes to mind...

[fastfredracing]

I used to tape my headers, and like stated above, the steel ones turned into dust in about 1-2 seasons. I also suffered an engine fire that I believe was caused by an oil leak that absorbed into the wrap and ignited when they got hot. No more header wrap for me.