Should I weld?

[cdorhout]

I need to add a 1/4" spacer between my factory cast RB25 manifold and my new turbo. The compressor is too big to bolt directly up, so I have 1/4" flange to use as a spacer.

My question is: Can I or should I weld this steel 1/4" flange directly to my cast manifold? or should I just run longer studs and two gaskets. I was gonna go the welding route until a welder told me it would crack.

I know some guys weld Wastegate flanges to their stock manifolds, so what should I do? Is it worth worrying about? I'm leary to run 2 gaskets cuz it makes for more places to leak.

[Sil240]

I would weld it.But to weld Cast Iron to Steel.You need a special Rod.I'm not sure but I believe the guy that did mine used Some Nickel alloy rod.

If you look at my bootled Turbo outlet/Dump in one of the other threads there's pictures.

I've seen people weld to Cast Manifolds before and they've held up for years.You just have to use the right rod and have a good welder do it.

[Carl H]

you'll need a proper stick welder and the sticks to suit but it can be done, just make sure the cast manifold is UBER clean and rust free.

[cdorhout]

Cool, that's good to know.I'll feel much better with a welded seam in there rather than another gasket.

I'll try to find another welder who has actually done it and knows what stick to use.

Thanks!

[240z4u]

I did not weld mine. and I used TWO spacers (flanges) and gaskets to make everything work.

I did it two years ago and never a leak. I had forgotten about it actually.

Later man - Evan

BTW, be prepared to open up the flanges/spacers. Mine had a smaller hole that I had to ream out with a die grinder. I also port matched my exhaust housing at the same time.

[integra7]

to weld 304 stainless to cast iron, use nickel 55 eletrodes

I used it when modifying my manifold for an external wastegate (welded stainless steel pipe to the manifold).

Also, many people run t3 flanges as spacers to get clearance for the compressor housing. No need to weld for that. I used a spacer to allow for clearance with my sc61 turbo, 2 gaskets....no issues.