Welding on 93 LS-400 exhaust manifolds

[GSMnow]

My engine swap is well under way, but we ran into a snag. The driver's side (left US car) exhaust manifold of my 93 Lexus LS-400 motor is running into the steering shaft in my 83 Celica. After much measuring, it has been decided that we will cut the manifold and re-weld it to clear the steering shaft. My question is...

Does anyone know for sure what material the factory 93 LS400 manifolds are made out of? It appears to be a low grade of stainless steel. My friend is a bit hesitant to cut it until he knows he can weld it back without leaks or crackng issues. If he needs to add some tubing, he also has to make sure it is comptible to weld to it. He can get T304 or T321 stainles easilly. The ower grade stuff G.M. was using on car here is also avaiable to a point, but not in the nice tight radius mandrel bends like the better grade tubing from Burns Stainless.

Any welding advice for the stock manifold material would be greatly appreciated.

Gary M.
[email protected]

 

[Peewee]

I know my 1990 UZS131 Crown headers were stainless steel, at least the guy in the exhaust shop who modded them for me said they were.

But I also am pretty sure that some of the other headers are cast iron jobbies.

At a good guess, I'd say if its not cast, then its stainless.

But I know I welded my ones with a normal arc welder.
I had to cut a bit out, and weld something else in to clear the steering shaft, and that was just mild steel that we welded back in.
Didnt look pretty by any means, but it worked.

 

[SCV8]

You may have to fabricate a sleeve, or ring to pass around, and weld onto the tube you're altering to provide a fresh, additional surface to weld to.
TIG, would be my choice.

 

[GSMnow]

He is going to use TIG and even purge the inside of the pipe with argon dueing the weld so it does not oxidise any further. They are tubing, and actually look in very good condition for 12 years old and 180,000 miles. I am starting to wonder if my donor car had a new engine installed, everything looks very nice for the age. My guy doing the welding is almost certain it is a stainless steel of some sort, so he will be using stainless rod and T304 pipe for any needed addition. Thanks

Gary M.