Hi All
Bought a speedster replica and I have to replace the muffler (it was hit on something, dented, and the seams were split). found the same one to replace it with, but found out the builder of the car modified the original (moved the tail pipe). I need to do the same modification to the replacement muffler. After I cut the tail pipe off, should I butt weld in the patch, or can I simply go with a bigger patch and cover the hole? Does the air pressure in the cannister make a difference on which method is used? I am a bit concerned about potential leaks if I butt weld and have a pin hole that I cant see.

The modification is not visible once the muffler is installed.

Thanks!
Scott S

I usually only butt weld when I'm doing body work. For frame restos and muffler repair overlap is ok.

It may also depend on the state inspection regs. Here in New Hampshire a patched muffler is not acceptable. If you are allowed to patch where you are than either method will hold the pressure, with the larger patch being easier to install properly. Good luck.

Doing a proper butt weld on a muffler is very difficult. If you can flange the area around the patch, you can hide it better. If you can't see it, then I wouldn't bother trying to flange it.

I've got a vice grip style flanger as well as a pneumatic flanger/hole punch. PM me if you need and help/advice Scott.

Thanks a million for the help/opinions. These patches will not be visible once installed, so getting the car through the initial inspection should be no more difficult than it already will be (being a replica and all).

Here is a pic of the existing look. The only difference in the new one will be ditching the stainless tip - it will just be raw steel painted with the correct white/grey muffler paint.

Now I have to figure out how to relocate the ebrake and get the wiper arms chromed. It has been fun working on this car. it is super clean - only has 800 miles since it was built in 2008.

Thanks again -