How much heat wrap?

[ISPKI]

Hey guys. I am expecting my MSA headers for my 280z to arrive early next week and I will be installing them next weekend. I would like to heat wrap them but I have never heat wrapped anything before. My question is: How much heat wrap will it take to wrap MSA 6-2 headers? I am probably going to shoot for the 2" wide stuff.

[EF Ian]

50 foot of the 2" wrap was more than enough to map my big 4-2-2-1 header on my civic, so should be enough for a 6-2

[Ont240]

My experence with an MSA header and wrap> don't. I burned one through in less than 2 years.

They are made of a very thin metal.

 I fabricated a SS heat shield and have run a new MSA 6-2-1 for the last 13 yrs without issue.

 Ceramic coating would be an alternative.

[ISPKI]

So how can the heat wrap burn through the headers? I mean, the temperature the engine produces is not even close to what you would need to do that. Although I love me some stainless and I love me some fabrication so a SS heat shield sounds like a sweet idea. Got any photos of yours? If I dont use the wrap on the header, then would it be beneficial to wrap the intake instead? I already have the wrap so I am sort of stuck with it.

[Sideways]

So how can the heat wrap burn through the headers? I mean, the temperature the engine produces is not even close to what you would need to do that.

 

Ever wonder why it feels "hot" when its 90 outside, and your body runs at 98.6(ish) degrees? Ever get too hot under a blanket at night?  Its heat dissipation. Its not about how hot something "is at the moment", its about where that energy/heat is going.  Header wrap insulates.  A wrapped header cant dissipate the heat as quickly as an unwrapped one. 

 

Wrapping the intake will work, at first.  Its insulation after all- Itll stop the heat from the exhaust and radiator from going into it.  But it works both ways.  Intake manifolds also get heat from the engine theyre bolted to- wrapping the intake will stop the manifold from being able to radiate that heat and itll run hotter than if you didnt have it.

[Tony D]

Header wraps hold moisture against mild steel headers when lukewarm...and the rust from the outside in much faster.

The internal heat stresses are higher due to above explained phenomenon...coupled with rust flakes forming thinned sections which heat faster and get to melting temperature faster than metal which is thicker, nearby.

 

And viola! Burn-through!

 

You can put a propane flame (which is never enough to melt steel, only make it red hot at best) into a 1/2" tube...it glows red.

 

Now start filing notches in the tubing and watch what happens in the narrowed sections!

 

Same thing, compounded by the wrapping.

 

It is not recommended for mild steel, untreated headers as most people won't accept replacing them every few years as a comsumable item.

 

Hell, most people won't do that with spark plug wires!

[mattb3562]

How about a ceramic coating over the headers to seal the steel from moisture? As that generally does not keep the engine bay as cool as advertised, you could then wrap the header. Not a very cheap way out, but definitely cheaper than fabbing SS.

[RebekahsZ]

I wrapped one and loved how much it cooled the engine compartment-could touch header with a bare hand. A hole blew thru it at the first bend from exhaust valve within a year. They speak truth.