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what's everyone's opinion on heat wrap?

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Old Nov 3, 2010 | 12:03 AM
  #26  
DriveFast7's Avatar
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Paint the headers with high temp ceramic paint to reduce rust. So it won't soak in moisture from the header wrap on damp days. Cook it in your oven, follow the directions. Then wrap it. Don't overlap the wrap too much, people like to wrap it so there are two layers but the instructions say to only do something like 1/2" overlap so the header won't get too hot.

I sprayed it with the DEI silicone spray. Supposed to protect it more but that spray is slowly coming off.

I use the Racing Beat aluminum heat shield too. Why not?
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Old Nov 3, 2010 | 09:49 AM
  #27  
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You must have a really really big oven. Headers won't come anywhere close to fitting in mine.
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Old Nov 3, 2010 | 09:17 PM
  #28  
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Most everything has been said. Here is what I would go by to make your decision - and as usual, it boils down to money.

Header wrap is cheap, a pain to install properly, ugly, can be dangeous and will shorten the life of your header.

A GOOD ceramic coating is expensive (realative to wrap), simple, can be asthetically pleasing and can extend the life of the header.

Don't wrap. Save up and coat IMHO.
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Old Nov 4, 2010 | 02:30 PM
  #29  
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Originally Posted by DriveFast7
Paint the headers with high temp ceramic paint to reduce rust. So it won't soak in moisture from the header wrap on damp days. Cook it in your oven, follow the directions. Then wrap it. Don't overlap the wrap too much, people like to wrap it so there are two layers but the instructions say to only do something like 1/2" overlap so the header won't get too hot.

I sprayed it with the DEI silicone spray. Supposed to protect it more but that spray is slowly coming off.

I use the Racing Beat aluminum heat shield too. Why not?
Originally Posted by rotarygod
You must have a really really big oven. Headers won't come anywhere close to fitting in mine.
+1, how the hell did you fit your header in your oven?
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Old Nov 4, 2010 | 04:06 PM
  #30  
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They might fit on the bbq pit or in the smoker!!!
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Old Nov 4, 2010 | 05:15 PM
  #31  
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its not hard to make a big oven, anyone that's done powder coating knows this.
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Old May 2, 2011 | 11:33 PM
  #32  
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Originally Posted by ultimatejay
+1, how the hell did you fit your header in your oven?
I **** u not it fit in my oven!@@! Pulled the top 2 racks out. The smell was horrible even with a box fan on the kitchen counter. Had to use EasyOff oven cleaner in there afterwards to make sure no residue is left.

But yeah, it fit in my oven. Newer GE gas oven.

I also fit that damn header in my dishwasher to clean it off. With CLR. Removed the upper rack. Worked bitchin'.
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Old May 3, 2011 | 06:09 PM
  #33  
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/\ Badass! Great resurection too. LOL!
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Old May 3, 2011 | 10:33 PM
  #34  
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Originally Posted by DriveFast7
I **** u not it fit in my oven!@@! Pulled the top 2 racks out. The smell was horrible even with a box fan on the kitchen counter. Had to use EasyOff oven cleaner in there afterwards to make sure no residue is left.

But yeah, it fit in my oven. Newer GE gas oven.

I also fit that damn header in my dishwasher to clean it off. With CLR. Removed the upper rack. Worked bitchin'.


I'm going to have to coat my downpipe now. Then wrap it. Then heat shield it.
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Old May 4, 2011 | 01:42 AM
  #35  
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I can update this thread. The GLC's header cracked at the engine flange. I think I'll swap it out to a manifold until I can redo the whole exhaust in 2.5" with an unwrapped header this time. Current exhaust is 2". Way too small and way too loud. lol
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Old May 20, 2011 | 04:53 PM
  #36  
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AZ

Originally Posted by t-von
Lets keep thing in perspective here. Do you know your EGT's? You sure it was good quality mild steel or a mixture of something else? If we don't know these things, then others can be fooled into thinking that MILD steel isn't a reliable metal. It has a higher melting point than stainless. Simple Google search below!

http://www.auto-ware.com/techref/meltpoint.htm

You need to be wary of the **** you find on the Internet. An engineering site quoted stainless at 2750 F and Carbon steel at 2600 - 2800 F.

http://www.engineeringtoolbox.com/me...als-d_860.html

So about the same. There are too many Wiki Pedia sites around.

GD

Last edited by gawdodirt; May 20, 2011 at 04:55 PM.
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Old May 20, 2011 | 11:36 PM
  #37  
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To hell with it. I decided I would used the wrap I bought for my headers. I bought the wrap over a year ago and I'm tired of looking at it as waisted money. LOL! We'll see what happens!
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Old May 24, 2011 | 08:31 AM
  #38  
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Originally Posted by speedturn
I have a peripheral ported first gen RX-7 road racer that I have been running for 16 years now. After a few years of racing, I wrapped the Racing Beat header and midpipes to keep the floor of the car cooler. After about 6 months of using it with the wrap, the exhuast pipe started rubbing against the rear axle. The pipes had warped, and drew forward almost an inch at the rear axle! I had to sawzall the rear section off the pipes just to finish that road race weekend out.
After that race, I unwrapped everything to see what had happened. The surface of the mild steel RB pipes were flaking. Thin, nickel to quarter size layers of steel had oxidized and flaked off the steel pipes. They looked horrible, like leprosy. My theory is that the sustained 1700 degree exhuast temp of my road racer had overheated the mild steel exhaust pipes because they were no longer getting that 100 mph breeze of air over them to cool them down.
I pulled those pipes off my racer, and installed a stainless steel header and made a new set of mild steel mid-pipes, and those have lasted for over 7 years with no wrap and no problems. No, I did not have any carb problems.
I took the set of heavy gauge warped, leprous Racing Beat header and pipes, straightened them out, and put them on my daily driver streetport 1st gen. Those old RB pipes are so thickwalled, that they are still holding up with 7 more years of street use. Those old RB pipes are now 16 years old!

PS - when I got rid of the wrap, I fabricated a new set of heat shields for my race car. I am a mechanical engineer, and I believe that a heat shield with an air gap on each side does a better job of reducing radiant heat transfer from exhaust pipes to chassis components than the wrap does.
This is exactly what happened with my headers. Granted I am also a race car and I run at full throttle for most of the lap and run for up to 3 hours at a time, but I blew a hole out of my header at the first bend. This all happened within 6 months from new. We took the header off the car and thought we could weld it up, but for at least 2 inches on either side of the blow out, the pipes had turned almost to sand stone. There was no weldable metal nearby. I ended up junking the headers.

I replaced them with a set of Racing Beat headers and added good heat sheilds to control and divert the heat. Under hood temps dropped a lot and the headers have been on the car for 12 years with no issues at all.

Personally, I wouldn't heat wrap the headers. I would ceramic coat them and build some nice heat shielding. I believe that they will last a lot longer and work just as well.

Eric
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