I am running a 1300 x flow and have already fitted a 1300 GT 4,2,1 manifold in the past. It cracked in a couple of places and as I have the engine out for modifying I need to redo it. I think I need two bends, 1 x 90 and 1 x 45 that I will need to cut to the required length so how do I join them? I presume butt joining and welding wouldnt be strong enough? Do I need to sleeve them on the outside? Also where can I get a flexible section to weld in to allow the system to move and prevent it cracking again?

What do you intend doing with the bends? Are they to replace the bits that have cracked?

If so, they'll be best butt welded as that's how they're usually made. But would it be possible to weld up the cracks as they are, if they've been caused by the exhaust being too solid?

Actually, any chance of a pic?

[Edited on 9/4/12 by DIY Si]

Most welded manifolds are but welded, a proper weld is as strong as the metal it's welded to.

My xflow exhaust is but welded, seems to be ok to me