EFI exhaust manifold cast STEEL or iron?

guhfluh

Famous Member
Anyone ever weld to one? My rear manifold is rusted and worn at the ball socket, and leaks. I'd like to weld different flanges on the ends of the manifolds, but not sure what material they're made from and I'm no welder to begin with. I don't have the equipment to weld or braze an iron manifold properly, but I might be able to hack together something if it's steel...
 
I'm not going to be of any help in regard to welding on new flanges, but I'll just give you the heads up that new OEM EFI manifolds can be had on ebay for just about $40.00. I bought a rear one recently but ended up using my old one because I didn't have a big enough hex wrench to remove the plug that's blocking the EGR port - and I managed to get the old one cleaned up well enough to reuse.
 

guhfluh

Famous Member
Well poo.

The price of a new one isn't a problem; I'd also like to use the manifolds if I ever get to put a turbo on and I don't care for the ball and socket design. I worry about sealing issues under pressure, heat, stress, etc. I also have this one ported already to match my head, which would save some time.

I guess I can still pay someone to weld/braze a flange on if I really want to.
 

bubba22349

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Don't use any brazing rod on it, it won't stay togeather. :nod:
 

arse_sidewards

Famous Member
Max_Effort":ftw7o1sc said:
Cut the ball part off and then mill it for a flat flange.

This.

I'd personally use the ball and socket though. It's going to be harder to blow it out than anything that uses a flange.
 

guhfluh

Famous Member
Max_Effort":3111nfvr said:
Cut the ball part off and then mill it for a flat flange.
Thought about doing that AND using a donut gasket with the stock ball socket pipes. Not sure if that'd be better?
 

Max_Effort

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Supporter 2018
guhfluh":39zynqta said:
Max_Effort":39zynqta said:
Cut the ball part off and then mill it for a flat flange.
Thought about doing that AND using a donut gasket with the stock ball socket pipes. Not sure if that'd be better?

Might work, might leak and blow out

I think either a good ball and good socket
Or
A flat milled manifold and a heavy, thick flange and a good gasket... MLS, or one with a good metal ring (like a head gasket).
 

Sevensecondsuv

Active member
I've had pretty consistent success welding on cast iron manifolds, including on the hot side of a turbo system. I use ER308 filler with with the TIG process (probably any filler with a high nickel content will work). Heat the cast piece up with a torch to at least 500 F before striking an arc. Then weld in small batches, no more than an inch at a time. Hammer peen the welds immediately and thoroughly. Use the torch to keep the remainder of the part hot between welds. Once welding is complete, use the torch to control the cool down rate; the slower the better. Done right it will hold together just fine
 

Shorty

Well-known member
I welder the flange on one of my manifolds when I built my truck ten years ago because I didn't like the way it pointed. I cut it off and cut a wedge shaped section out and beveled it and tacked it, set it on the wood stove for an hour and welded it. I used the lincoln 180 mig with the gas-less flux cored wire in it because that was all I had available at the time. It welded nice and smooth hardly any spatter and has worked without a problem on the truck ever since. Now that I have a tig I would use that with a good high nickel filler rod but the pre heat and good surface prep and fitment are critical.
 
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