New Exhaust Plus Complications

After a few weeks of waiting there was finally an alignment of decent weather and the weekend. That meant as soon as a got done with a few household chores I was able to start the process of taking out the old exhaust and putting in the new one. This system includes the resonator, a muffler, and the various pipes that connect them.

First a quick note of resonators vs mufflers. They are similar to each other in that they are responsible for mitigating exhaust noise. The main difference is that the resonator does not quiet the exhaust sound. Rather it “tunes” the exhaust sound in a way that makes the muffler’s job easier. That way the muffler can be designed to muffle a much narrower set of frequencies which means a quieter ride with less of a hit on performance.

Removal

The whole process starts by jacking up the rear of the car onto jack stands. Next I had to remove the clamp that connects the resonator to the catalytic converter pipe. This clamp was hideously rusted and was almost just a clamp shaped lump of corrosion. I blasted it with WD-40 and used a breaker bar with a 14mm deep socket to get the nut turning. It took some muscle, and boy did that nut scream as it turned, but eventually I got both sides off far enough to be able to move it out of the way. I then got out the rotary tool and used a cut off disc to finish it off. I wasn’t going to reuse them, so this was the much faster and easier method.

Next I removed the two rubber donuts from which the resonator hangs beneath the car. They looked to be in pretty good shape but the kit I bought had sprayed the sleeve on the intake side that fit over the catalytic converter pipe with Kroil and let it soak a bit. I figured there was a lot rust under that sleeve that would be holding fast to the cat’s pipe and I wanted to make it as easy as possible to come off. After a few minutes of waiting I started in with the hammer, whacking the front face of the resonator. The good news: it did move a little bit off the cat’s pipe. The bad news: a weak section of the downpipe that was hidden under a heat shield snapped and sent it crashing to the ground.

Obviously that’s going to have to get fixed. I’ve ordered a stainless steel sleeve to couple the parts back together, but what with this pandemic going on it’s going to be a bit slow to arrive. In the meantime I’m going to disconnect the section attached to the catalytic converter, clean it up, and replace the gasket and other bits (which I’ve also ordered).

So, moving from that I sprayed the resonator with more Kroil and continued to hit it with the hammer. After some prying with a flat head screwdriver and way more whacks than I thought it would take the dark thing finally came off. After unhooking the rubber hangers on the muffler I pulled the whole thing out to take a look.

The resonator was in terrible shape and definitely needed replacing. The rest of it wasn’t in particular great shape either. I dragged the whole assembly into the back yard and used it as a pattern for putting together the new one. I made sure not to tighten the clamps too much so I’d have some wiggle room to line everything up.

Installation

As they say, installation was the reverse of removal. I hung the muffler first and then the resonator. The only real difficulty was that the new rubber donut hangers were tough as heck and a real pain to stretch. To test the system I loosely lined up the parts of the broken downpipe and secured them with the old heat shield and started the car. It was obviously still quite loud, but exhaust was coming out of the tailpipe. Once I get the downpipe back together and the gasket between it and the catalytic converter replaced everything should be nice and quiet.