Header wraps

[tom jaffeux]

Who is wrapping their header? What are your results with the heat in the engine bay ?

 

[Don Frelier]

Works well for cutting the heat
Wrapping is pretty painful, but I was doing it when it was in the upper 80s.

 

[sam dupont]

I put a v8 into a car that overheated the open cockpit with the original 4 cylinder. The car came with no insulation and rubber mats on the floor. Wrapping the ram horn looking manifolds, I found water soaked header wrap lightly stretched went on nicely. Being an artist, I clamped with concrete tie wire. I got the idea from watching Insulators wrapping in oil refineries.

 

[gkent]

I works till the wrap is heat soaked - then it doesn't. If you think its an insulation, touch it and give us an update !!

 

[j-c-c-62]

Who is wrapping their header? What are your results with the heat in the engine bay ?

It is a rather short-sighted gain IMO.

Reason being and my experience:
"Thermal Fatigue
Thermal fatigue is a specific type of fatigue failure mechanism that is induced by cyclic stresses (thermal expansion and contraction) from repetitive fluctuations in the temperature (heating and cooling) of equipment. This type of fatigue is very important especially in power engineering, aeronautics and automotive engineering.

Thermal stresses arise in materials when they are heated or cooled. Thermal stresses effect the operation of facilities, both because of the large components subject to stress and because they are effected by the way in which the plant is operated. On cooling, residual tensile stresses are produced if the metal is prevented from moving (contracting) freely. Fatigue cracks can initiate and grow as cycling continues." What is Thermal Fatigue - Definition | Material Properties

Header Wrap increases the temperature of the underlying metal and that larger temp gradient as it cycles accelerates thermal fatigue.
Or everything has a price still holds true. Crumbling in your hand is the final price, only a matter of when.

 

[PurpleBeeper]

Who is wrapping their header? What are your results with the heat in the engine bay ?

My fuel no longer boils, so it worked for me

 

[gkent]

My fuel no longer boils, so it worked for me

LOL !!!

Every race car on the planet has header wrap. But they don't give a **** about under hood heat OR noise. So why do they do it ?? Because the contained heat eguals horsepower - PERIOD. And to J-C-C's point, racers don't give a damn about the longevity of a set of headers - as long as they last the race they're happy. Header wrap is just a failure waiting to happen.

And for what it's worth, the engine compartment gets no hotter with headers than it does with iron manifolds. Once either are up to temp they both radiate the same amount of heat. The iron will take longer to heat up but also longer to cool down.

 

[j-c-c-62]

And to J-C-C's point, racers don't give a damn about the longevity of a set of headers - as long as they last the race they're happy. Header wrap is just a failure waiting to happen.

I believe back in Dan Gurney's time the driver's mindset was, as long as they crossed the finish line with their steering wheel, everything else is fine.
I don't dispute that claim, but feel those less motivated with a streetcar. should know there can be a hidden cost in using race car solutions in non-race cars. longevity being one. Using SS greatly reduces heat wrap concerns, but does not eliminate it.

 

[RemCharger]

The wrap thing is from the 90s-- no one at a race track uses that stuff anymore. The worst part about it is prematurely rotting out headers ( I've seen holes blown right out), and yes racers are concerned about longevity of expensive headers.

 

[sam dupont]

My car is a street legal racer that gets less than 1,000 miles per year. The iron manifolds and thick wall exhaust should last.
The system is two factory LH manifolds (RH reversed) that hug the block. The RH side goes forward and around the oil pan, then meets the LH in a wye continuing next to the driveshaft and out the back; The stock configuration. The only other option was side dumps, but I like sleepers. So much so, I considered putting a dump on one bank to make it sound like a four cylinder that was a piece of crap. My hope for the wrap was to keep the heat away from my oil pan more than cabin comfort.

 

[j-c-c-62]

With that goal, there are other solutions, almost as effective and less long-term destructive IMO, such as a simple thin SS half shield hose clamped to the exhaust with any airgap, and/or gold heat reflective tape applied directly to the oil pan, etc

 

[gkent]

A heat barrier with an air gap is the best solution for protecting select items ... oil pan, starter motor to name two. Look at what they use under any late model car between the exhaust and floor pan. Go to a wrecker and find a low milage wreck and snag one of the shields and make what you need out of that.

 

[dadsbee]

Knew a group of aircraft builders that wouldn't listen and wrapped all of their expensive exhaust systems on their RV's. All that was left about 3 years later was a tube made of the wrap, and no steel inside !

 

[gkent]

LOL !! The kids raced karts. We wrapped the headers 'cause every fraction of HP counts. But we'd go through three or four pipes a year. No big deal at $25 a pop BUT I know what prblems it creates! The downside was if your pipe broke during a race you were DQ'd. That was worse than the expense.