Are the OEM headers really double walled?

[XSPastor]

Has anyone ever cut up a set to verify this? I know they don't "blue" as easily as some aftermarket pipes and that has always been attributed to the assumption that they are double-walled but I want proof.

[trbig]

Well... I'll tell you what. Unless someone beats me to it... this evening, I have a set that I need to throw away, so I'll cut them and see. I personally think they are just a heavier metal than MAC or Jardine.... but we'll find out. I remember John had said Kat had a rattle in a pipe they couldn't track down, and that it ended up being the inner wall of the pipe coming loose. BUT.. I don't remember if that was on her FJ, or an XS.


Tod

[prometheus578]

"Go fer it, TRBIG!"

I've never looked into that matter, either.
Let us know what you find....
(Not that we'd believe you, anyway.)

[Dennyz]

Yes, they are. That is why they are so heavy and don't typically blue.

[xschop]

double wall

the Jardines I have are double walled....

[XSPastor]

The Jardines I just bought are only double for about 2 and 1/4 inches at the flanges.

[trbig]

Double Walled...

Well... It seems to be true!!





Sorry it took a day longer to get back to you.



Tod

[TopCatGr58]

Well, there you go!

For once, Tod, being a "CUTUP" had it's benefits!!

T.C.

[fredintoon]

Too late!

Hi trbig,
I do hope you were going to saw up that pipe anyway, rather than sacrifice it to Tim's curiosity. If you look at the straight part of the cut pipe maybe half-way to the Y-connection you will see the vent hole in the outer pipe and there should be another one up by the head clamp. Looking into the vent hole and seeing the outer surface of the inner pipe is proof enough that the system is double walled without resorting to a hacksaw.
Then you could have had that rusty system sandblasted & sprayed black and it would be in better shape than mine.

[trbig]

Those headers were junk... especially the collectors. I took them to a guy to get nickel (Nickle?) plated. After sandblasting and an acid bath to get the carbon off/out, there were several pinholes found where the metal had rusted through. If the metal was that thin, I didn't want them.

Tod

[XSPastor]

Trbig, You are the man!
I hope I can return the favor some day and cut something in half for you! The Macs say in their literature that the first 12 inches of the headers are double walled to help minimize blue'ing. The Jardines I just bought are double walled for 2 1/2 inches! Once again, OEM is the best. If my mufflers weren't so badly cracked I'd keep the OEM system because the headers are in great shape. The specials don't take too kindly to slip-ons either or I'd try that. The pipes flare right from the weld all the way to the end of the muffler. If I was a welding man, I'd give it a shot but I haven't welded since high school metal shop! Thanks again Trbig; I owe you one!

[Dan Hodges]

Re: Double Walled...

Originally posted by trbig
Well... It seems to be true!!





Sorry it took a day longer to get back to you.



Tod

I have never actually seen one of the stock pipes cut in half, untill now. The only aftermarket pipe I have ever seen that was made this way was a Super/Trap. I have a spare Kerker 4 into 1 and it is of single wall construction and I also have a half a dozen others that I have bought/secured over the years and they all appear to be of single wall construction. The Super/Trap header section without the megaphone muffler is about 3 pounds heavier than my Kerkers minus the meg and I can only assume this is because the Kerkers are single wall. Back in the disco era, this was a big selling point for both, Kerkers because they were light and Super/Traps because they were double walled and didn't turn blue. All of the Macs, Kerkers and Jardines that I have ever seen turned blue rather quickly including my original Kerkers however you can send them to Jet Hot coatings and have them coated in what they call Sterling silver and they will not turn blue, crack, chip or whatever. The Sterling is not quite as shiny as chrome but it's real close. As long as your pipes are not completely trashed out, the Jet Hot deal will make them like new. The Jet Hot process also coats the inside and after the process the pipes do not radiate nearly as much heat, it's a killer deal. Thanks for your picture, because now I know................... for sure. Dan