Exhaust: Exhaust relief...

[62champ]

I am only an intake/exhaust manifold gasket away from getting my new stainless exhaust put on my 60S-W4.

Question is about exhaust relief cuts. In some generic threads on other forums about getting pipes to go together with the best change of there being no leaks, many people state that there needs to be relief cuts in the outer pipe.

This would constitute the muffler on the new system. Both the header and tail pipe slide inside the muffler's outlets.
Does the muffler outlets need some relief cuts? Is so, how many and how deep?

Photo is of the inlet on the muffler and shows what I am dealing with:



Thanks ahead and happy Labor Day to everyone (Labour for those who speak the Queen's English)

[Mike Van Veghten]

Correct.
If you think about it, you need to make the outer tube smaller...to form a tight fit to the inner tube. You would have to have a way of putting a HUGE load on the outer tube top get it to crush on to the unner tube...correct..? Since a circle is pretty freaken strong when it's being crushed either lengthwise, lever arm or in a 360 degree circle. Takes a large load to crush it.

So...yes, sure...you have to help it be crushed. You do this by cutting releif cuts/slits into the tube to enable it to be easilly crushed in an even, 360 degree circle.
From one to xxxxx cuts can be used. Normally one or three cuts are used for a nice even crush. Two slits can be used but they sometimes do not bend uniformally as does one or three.

Do not leave the cuts/slices open or exhaust gas spitting will occure. Slide the outer tube well past the cuts over the inner tube.

Mike

[RadioRoy]

The muffler shops around here like to weld the joints. I have had them try to weld a joint that was several sizes off. I asked them to make a spacer from an intermediate size of pipe and they did that for me.

Perhaps welds do not hold up as well in the rust belt, but since we no longer drive our cars in the salt, that may be a moot point.

As an aside, exhaust systems last for 15 years out here in the San Francisco bay area.

[Tom Bredehoft]

I simply slid the smaller pipe inside the larger pipe and tightened the U clamps. Tight. No leaks, it holds nicely.