Heat wrap on Headers?

[BXSS]

I got a set of stainless steel E/L 4-2-1 turbo headers off a well tuned EJ20K.

These things were on the 20K without any form of heat wrapping.

Should I heat wrap them when I try them on my car, or should I leave them the way they were on the other motor?

I heard that heat wrapping helped to crack BORLA na headers (but it seems like looking @ those caused cracks too), but these have slip joints in 3 areas that should allow for some expansion w/o cracking.

[ciper]

Most everyone will agree that coated pipes are far superior.

For the price however I think exhaust wrapping is a wonderful thing. Most of the cracking issues are with cast parts rather than SS parts. Just make sure to buy the spray can of sealant so the pipes last longer.

[BXSS]

Yeah, I believe ceramic coatings are better too but I want to be sure this mod makes the car quicker before I spend money on a coating ($175+ @ Swain coatings here in NY -? if they will work with a used part) for it.

I have DEI heat wrap & heat wrap paint just laying in the garage so using them would be free :)

[ciper]

I say wrap the headers and up pipe but nothing else. Make sure to have 50% overlap so every area has two layers of fabric. Also get the wrap really wet before applying it (squeeze out extra water).

When you say heat wrap paint do you mean the sealing spray that "sets" the wrap and makes it hard?

[BXSS]

Yeah its the silicone spray that is supposed to help to keep the wrap from rotting...

I wonder why these headers were not wrapped by the guy in Japan who bought them?

[206er]

some say to leave the first 3" or so of primary bare. I dunno about that. I'd go ahead and wrap em if you have the stuff lying around. if they crack you can just reweld it.

[Aerotech]

It will probably only last you about 1.5 years... the exhaust is the lowest part of the front of the engine, my wrap got worn away in short order by curbs, snowbanks, and general road debris. Once you lose a section, the whole thing starts to unravel.

[ciper]

You must not have used enough sealant on it if it started to unravel. I think most cans recommend at least 3 coats!

[BXSS]

I wrapped the headers this weekend - they came out nice...

I also had a problem with ripping heatwrap on my Impreza.
I was playing in the snow/ice & snagged a 6-8" section of heat wrap on the OEM "y"pipe.

I'm going to buy a 4x8' section of 1/8th" aluminum & make skidplates for the Impreza & LSS to avoid that problem this winter.

[bmxpunk]

What heat wrap did you use? I am coating my TS headers/ uppipe inside and out but I was going to wrap over them as well.

I also got a skid plate for my car.

[BXSS]

I used DEI on my headers & OBS's UP & DN pipes in back in '04 & its is still hanging on (used DEI's silicone heat wrap coating/paint too).
I used DEI on the Y-pipe & a scrape caused a tear, but with a skidplate all will be good.

I have to get/make a skidplate soon as I have a Canton Billet oil filter that is LONG & sits about even with the bottom of the "Y" pipe.

[createnew]

How many feet of that heat wrap do you need? I got a 25' X 2" roll for mine...

BTW I haven't put these on yet, but I got an awesome looking header and up-pipe combo that looks exactly like agancy power's header. The best part is, it was son;y $140... shipped!!
Compared to the agency power's $560 price tag or borla's similar design header for about $700...

[ciper]

Remember that you are supposed to have quite a bit of overlap. When you are finished the entire pipe should have at least two layers of wrap in every area.

[scuzzy]

Remember that you are supposed to have quite a bit of overlap. When you are finished the entire pipe should have at least two layers of wrap in every area.

I've been told (and instructions say the same) that 1" wrap should have no more than 1/4" overlap, now that being said, achieving that in every single spot is a bit difficult, sometimes you wrap more in a specific area, never the less.

here's the result from my header wrapping:





I sanded down the cross pipe and up pipe, painted them with VHT and cured them in the oven at 200F for a while, then wrapped them with 25 foot of 1" wrap from DEI; I came up a little short (driver side cast iron header thingy is using some old wrap). Used stainless steel ties you can get at any Harbor Freight Tools store.

[BXSS]

Nice job.

[scuzzy]

Nice job.

It is nice, I can put my hands within 1" of the primaries without getting burned, you can definitely feel the heat; but it's not too hot to be so close.

[tahiti350]

biggest problems I've seen with the wrap is split pipes (embrittlement) due to the heat the wrap retains. this was on new uncoated steel tube headers (small block chevy). I had 2 sets in a row that basically shattered near the collector within 3 months of install.

The header wrap voidd the warranty...

[scuzzy]

biggest problems I've seen with the wrap is split pipes (embrittlement) due to the heat the wrap retains. this was on new uncoated steel tube headers (small block chevy). I had 2 sets in a row that basically shattered near the collector within 3 months of install.

The header wrap voidd the warranty...

Well. Mild steel is fragile stuff. My down pipe was originally ceramic coated and heat wrapped and after about a year of use (and a year of sitting in my living room) the wrap had held water so well (since the down pipe doesn't get nearly as hot as the primaries do) that the mild steel had started rusting THROUGH the ceramic coating.

It took a lot of sanding to get rid of the rust, and even then I could see fracture lines in the surface. I took it to someone to have the O2 bung welded in and he informed me not to wrap it, so I just sprayed it with VHT paint and left it at that.

I wouldn't wrap anything other than stainless steel or cast iron - but even cast iron holds heat very well. Mild steel however is pretty fragile stuff.

[tahiti350]

Just caught the Stainless Steel part, should be okay for a while, but will still embrittle eventually. Cast iron, now that's a different story altogether

[Adam West]

Had a long email thread with Jeremy at Crucial Racing about not using heat wrap on coated pipes as it 1) overkill 2) holds water and which destroys the coating and rusts the pipes...

"DO NOT wrap the downpipe! One, yes, it's total overkill. But more importantly that wrap will probably destroy the coating and it might cause the pipe to crack. It's just too much heat retention. The coating is already more effective than wrap is, and doubling up like that is just too much and can cause metal fatigue. Even the companies that make the wrap specifically say not to wrap parts that are already thermally coated for that reason. And wrap is extremely tough on whatever is underneath it because of how it traps moisture and starts to eat its way into the metal... it'll eat through the coating in the same way I'm sure."...

http://www.crucialracing.com/products/

[dirtyhandssubaru555]

the only problem i have ever heard of is from people getting to many layers/to thick of wrap and it causes hot spots on the pipe and there for the pipe fails, i have never heard anything about moisture but im sure it doesn't help

[coclodile]

[url=http://www.steel-pipe-tube=manufacturer.com]steel tube[/url] is very important .galvanization also very important

[94SS_Canada]

I didnt Even Seal my wrap, but i put enough clamps for it to last through WWIII

[93forestpearl]

My exhaust manifold has been wrapped for two years without any spray sealant, and it has been fine. If the car sits a lot I can see how it will hold moisture, but if you drive the car daily there won't be moisture in it. It doesn't take very long for anything to burn off, like coolant, lol.


When I think about it, the silicone spray lends me to believe that moisture will get trapped under there even worse, since it will have a hard time getting out, verses plain jane header wrap.