I recently put in MSA 3-2 header (with a Y-tube obviously) and had the rest of the exhaust professionally done all the way back--everything welded EXCEPT the two header pipes into the Y-tube. I intended to clamp this joint. It is a swaged fitting that fits really snug and probably seats at nearly 2 inches deep.

It is now a few weeks later, and I am getting around to installing a clamp on this joint. I notice from the paint scraped off the joint that this joint is moving at least 1/2 inch. I am assuming this is during normal heating-cooling expansion-contraction.

Should I clamp? If I do, where is this movement going to go? Will clamping this joint cause undue stress on the header/head connection?

steve77

If it isn't leaking at the joint, it may be a good idea to leave it as is. Since you have the rest of the exhaust welded you have no other place to allow for a little movement from expansion/contraction or the movement of the motor in the mounts. If you have everything solid in the exhaust you may stress the header mounting flange when the engine twist in the engine mounts. I'd leave it the way it is.

There are kits you can buy (or have fabricated) where tabs are welded to the header and then the y-collector to hook heavy springs on to hold things together all while allowing for expansion/twisting.