Mark, Using a mild steel filler material (mig wire) will work just fine on that "high" quality stainless steel Borla uses on their headers. The weld and adjoining area will oxidize (rust) because those areas aren't "304" or "308" stainless. If you do a good job of welding and get proper penetration into the parent material the weld strength should be adequate for as long as you will care about it. The weld areas will be a little bit weaker than the parent stainless. To fill that hole in the donut area, if you change your mind and keep it, just flatten a section of copper water pipe (M) or (L) will work just fine and clamp it behind the hole. Then use your mig welder to slowly fill in the area, letting it cool periodically so that the filler material doesn't fall out from being so dang hot. The crack at the 2-1 joint may give more trouble in the future, just because it is a higher stressed area, or flawed for some reason because it already cracked once. Bevel the crack at a 45 to 60 degree included angle with a grinder and drill a hole at the end of the crack. Bolt the thing to the engine without a gasket, protect the painted surfaces and the windshield from spatter, or bolt it to an old head and weld the crack and drilled hole. Don't leave any under cut along side the weld, as this will cause a stress raiser and the crack will be back next week, just a few millimeters to the side of the original crack. Further note, if this crack is not on the flange itself you shouldn't need to bolt up to a head. Relieve the stressed areas by heating the weld and adjacent areas to about 700 to 1000 degrees Fahrenheit and let them cool slowly. The big key to keeping the crack from coming back is relieving the stress. Borla probably claims about 15 to 25 horsepower gain. That's probably standard for a normally aspirated inline 6. Hope this helps. I would love to see your 69 American. Got any photos you can send? Armand 70 Javelin, 304, T5, 2.87 axle ----- Original Message ----- From: <Wrambler242@xxxxxxxxxxx> To: "XJlist" <xjlist@xxxxxxxxxxxxxxx>; "Strokers" <strokers@xxxxxxxxxxxxxxx>; "AMC-DelMarVA: yahoogroups.com" <AMC-DelMarVA@xxxxxxxxxxxxxxx>; "AMC List" <amc-list@xxxxxxxxxxxx> Sent: Wednesday, March 12, 2008 2:03 PM Subject: [Amc-list] welding a Borla > Just got a freebie Borla exhaust header! > It's got a hole in the donut seal area from a torch burn and it it is cracked at the 2-1 joint. > It's not too bad and I want to weld it up and either use it on my wife's XJ or the American. > Anyone have nay tips on what I should use to weld it up with? > I welded up a factory HO tube with my mig and the commom [forget designation] mild steel wire. > It is holding up fine. > Should I do the same with this? do I need to find a special wire? Sub it out to a welding shop? > send it back to Borla and see if they will fix it? > I sent this out to several groups as I figure someone will have an idea. > Left to my own devices, I'd probably just weld it with what I have as honestly the "stainless" of this Borla does not look one bit better than the stuff Mopar used on the HO tubes!!! > It's still a nicer looking piece. > I'll probably ditch the donut area on it as I did the one on the American. > Any idea of what gains Borla claims out of one of these? > Can't beat the price:] > > -- > Mark Price > Morgantown, WV > 1969 AMC Rambler, 4.0L, EFI, T-5 > 2004 Grand Cherokee Laredo, 4.7L, Quadratrc II > " Chronic Pain Hurts" > _______________________________________________ > Amc-list mailing list > Amc-list@xxxxxxxxxxxx > http://splatter.wps.com/cgi-bin/mailman/listinfo/amc-list > > > > -- > No virus found in this incoming message. > Checked by AVG. > Version: 7.5.518 / Virus Database: 269.21.7/1325 - Release Date: 3/11/08 1:41 PM > > _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://splatter.wps.com/cgi-bin/mailman/listinfo/amc-list