So I spent a few days searching for a muffler for my 2014 Express CC. I finally settled on the Flowmaster 50 HD but I couldn't justify spending $360 on the direct fit model, so I spent $150 on the universal muffler instead. I'm a bit of a hard core DIY'er. My previous project was a 99' Mitsu Galant that I installed a complete Mitsu Evo drivetrain in and converted the car to AWD in my garage with a few jacks and a welder. So I figured, how hard could it be to install this muffler?
So here is the muffler itself unboxed
I measured the outlets on the Flowmaster and the distance from center to center was only about 5/32" shorter (closer together) than the stock muffler. I also measured the overall length and decided the easiest way to make this work would be to mimic the stock muffler overall length, for an easier install.
I started by welding 2 1/2" ID to 2 1/8" ID adapters on to the outlets of the muffler. I cut two slits into the smaller side so that I can clamp them down good to the stock pipes. Once I had this figured out, I lined it up next to the stock muffler and took measurements to determine how much tubing I had to add on the inlet side.
Then welded a piece of 3" steel tubing to the inlet side of the muffler and a 3" OD to 3" ID transition adapter. I also cut two slits into the larger side of the adapter.
I just welded this up quick, if I had been welding stainless I would have taken the time to clean the joints more thoroughly and back purge the TIG weld for a nicer looking and corrosion resistant weld.
Once I had the overall length exactly the same as the stock muffler, I had to figure out what to do about the hangers. If I had a working MIG welder (mine broke), I might have just did the hangers with the muffler on the truck already, but since I didnt have a MIG and since I absolutely hate trying to use my TIG laying on my back, I came up with this solution.............
I built a quick jig using the stock muffler as my reference to locate the hangers. I used the outlets on the stock muffler to mount the jig since I knew the outlets on the flowmaster were in the same position length wise and only 5/32" closer width wise, which has no effect on the hanger location.
Then I bent up two pieces of 1/2" steel rod to make my hangers. I just put the rod in a bench vise, hit it with 200 amps from the TIG welder for about 10 seconds to make it red hot and hit it with a mallet to get a 90 degree bend. I could have heated it with a torch but I already had the welder setup and I was being lazy.
I used the jig to locate the hangers, used vise grips to hold them in place while I welded them and then used a piece of rod to join the hangers as a brace. This jig will come in hand as I will be helping two of my friends install mufflers similar to this on their 4th gens in the near future. I also ran a small bead of weld around the ends of the hangers to help them stay secure in the rubber mounts.
After that I just sprayed the welds with some high temp rustoleum flat black paint and installed the muffler. It fits like a glove.
I purchased the 3 adapters and muffler clamps from the local AutoZone for about $20 and the 1/2" steel rod from Home Depot for $10. The piece of 3" tubing I had laying around in the garage, that was free. So I'm into the whole muffler job for about $180 and 2-3 hours worth of my own labor. At the end of the day, I'm very happy with the finished product. I tried to link the video/sound clip via photobucket but it wont work.
So here is the muffler itself unboxed
I measured the outlets on the Flowmaster and the distance from center to center was only about 5/32" shorter (closer together) than the stock muffler. I also measured the overall length and decided the easiest way to make this work would be to mimic the stock muffler overall length, for an easier install.
I started by welding 2 1/2" ID to 2 1/8" ID adapters on to the outlets of the muffler. I cut two slits into the smaller side so that I can clamp them down good to the stock pipes. Once I had this figured out, I lined it up next to the stock muffler and took measurements to determine how much tubing I had to add on the inlet side.
Then welded a piece of 3" steel tubing to the inlet side of the muffler and a 3" OD to 3" ID transition adapter. I also cut two slits into the larger side of the adapter.
I just welded this up quick, if I had been welding stainless I would have taken the time to clean the joints more thoroughly and back purge the TIG weld for a nicer looking and corrosion resistant weld.
Once I had the overall length exactly the same as the stock muffler, I had to figure out what to do about the hangers. If I had a working MIG welder (mine broke), I might have just did the hangers with the muffler on the truck already, but since I didnt have a MIG and since I absolutely hate trying to use my TIG laying on my back, I came up with this solution.............
I built a quick jig using the stock muffler as my reference to locate the hangers. I used the outlets on the stock muffler to mount the jig since I knew the outlets on the flowmaster were in the same position length wise and only 5/32" closer width wise, which has no effect on the hanger location.
Then I bent up two pieces of 1/2" steel rod to make my hangers. I just put the rod in a bench vise, hit it with 200 amps from the TIG welder for about 10 seconds to make it red hot and hit it with a mallet to get a 90 degree bend. I could have heated it with a torch but I already had the welder setup and I was being lazy.
I used the jig to locate the hangers, used vise grips to hold them in place while I welded them and then used a piece of rod to join the hangers as a brace. This jig will come in hand as I will be helping two of my friends install mufflers similar to this on their 4th gens in the near future. I also ran a small bead of weld around the ends of the hangers to help them stay secure in the rubber mounts.
After that I just sprayed the welds with some high temp rustoleum flat black paint and installed the muffler. It fits like a glove.
I purchased the 3 adapters and muffler clamps from the local AutoZone for about $20 and the 1/2" steel rod from Home Depot for $10. The piece of 3" tubing I had laying around in the garage, that was free. So I'm into the whole muffler job for about $180 and 2-3 hours worth of my own labor. At the end of the day, I'm very happy with the finished product. I tried to link the video/sound clip via photobucket but it wont work.
