I have an exhaust system made up of parts I got for free being flowtech headers and a flowmaster exhaust, the exhaust is clamped on very sloppily and the rest all the way to the engine is welded, the pipe is getting rusty by the muffler where it attaches and the welds all have very minor holes, very small puffs of air. These holes despite their size appear to be causing nearly half the exhaust and sound to be lost before it makes it to the muffler. I have tried repeatedly to fix these holes with more weld, but it just doesn't work, they still puff. I have fixed a few, but not by much. Is there any other way to patch these pinholes and the big rust holes in the back? I heard there was a putty you can get for exhaust patching but it doesnt last. I want this car to sound mean like the car these parts came out of sounded. It was all welded together on the other car too which is why it isnt bolted together.

Any ideas on patching holes without welding?

 

The patch stuff I think you are referring to is called Muffler Cement and NO it doesn't work at all. I would just cut the section out just before all this rust and replace it. If you just keep welding and welding it will eventually fall apart on you, plus it'll look a whole lot better.

 

I see, thanks for the input! I'll get around to fixing it all one day