Gibson Cat-Back Exhaust for YJ's

By James Hasler

 

After my stock muffler and tailpipe were damaged after running over some debris kindly dropped by a truck on the highway, I went shopping for an aftermarket exhaust. I knew my 6 cylinder would never sound like the V-8 in my ZJ, but I wanted a deeper sound and hopefully some more power. Also, since I abuse my YJ quite frequently, I wanted something that could take a beating and be relatively inexpensive so Borla's thin, although beautiful, stainless steel mufflers were out.

I decided that a Gibson's cat-back would be it. The system is made of 2.5" diameter, aluminized steel, mandrel bent tubing (a stainless steel version is availabe) and comes with everything you need. The system even comes with a 3" stainless tip. As with all exhaust system work, getting the old one off is what takes the most time. Here's a shot of the Gibson system in place.

Here is a shot of the tailpipe without the stainless tip. It is flush with the gas tank skid plate and I have never come close to hitting it on anything. Both the tailpipe and stainless tip are slashcut. I had the stainless tip on for a while, but after beating it flat on a couple of occassions since it sticks out quite a few inches, I decided that I was going to do damage to other parts of the exhaust if I kept it up.

As for power gains, I always do my usual test of finding a grade that I used to have to downshift in order to maintain speed. With the exhaust installed, many of these grades I can now maintain speed in overdrive. So, I'd say there are power gains.

As for the sound, it is deeper and I like that. However, there are places in the RPM band where it resonates. At times this sounds very good but it also makes it louder which can be annoying. I think this is probably more due to having an open topped Jeep than anything else. If you're looking for a bit more power and a deeped sound, Gibson makes a nice system.