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Cat-Back Exhaust System Installation

I'm writing this Cat Back install up AFTER doing one myself and making quite a mess. This is not how I did it, but it's how I'm going to do the next ones!

Time Required:
1-2 hours

Tools Needed:

  • Some kind of automated saw (be it a big reciprocating sawzall) or an electric jigsaw
  • Metal-cutting blades for the saw (having 2 or 3 spare blades is a good idea
  • especially since it's just a few bucks for a couple of blades)
  • Dremel with a cutoff wheel and lots of replacement discs (20 heavy duty discs cost $6 or so)
  • PB B'Laster (it's like WD-40 but better
  • WD will work in a pinch)
  • Eye protection goggles or glasses
  • Screwdriver to help shimmy those pesky rubber hangers off of the mounts on the exhaust system
  • Floor jack
  • jack stands
  • Protective hand gloves


    Stock system removal:
    1) Set parking brake, and put car in neutral or park
    2) Raise and support rear of car, use jackstands to hold car up safely.
    3) Put your protective eyewear on, and crawl under the car.
    4) Soak all 5 rubber hangers. There's one near the tailpipe, one up and under the rear suspension, one attached to the middle muffler (look up under the muffler, it's there), and two near the flexpipe flange up toward the engine.
    5)Take your reciprocating saw, and cut the exhaust somewhere close to the rear suspension, between the middle muffler and suspension preferably
    6)Using the screwdriver to pry with, carefully remove the rear resonator and tailpipe. Be careful when prying with the scewedriver, you can injure yourself. do not rip or damage the rubber hangers, they will be used to hang the aftermarket exhaust system later on.
    7)You may wish to lower the rear of the car and raise the front for the following steps.
    8)Crawl up near the flex pipe flange, and cut the bolts off with the dremel cutoff wheel. This could take some time, patience, and you may break or wear down as many as 4 or 5 cutoff discs per bolt. Your best bet is to cut across the bolt first, turning it into a "stump" and then cutting perpendicular to the flange, to cut the whole nut and bolt in half. This will get the bolt and nut off without any problems. If the nut doesn't split and fall off, then use the screwdriver in the groove you made to help pry the nut off. If that doesn't work, keep grinding on it with the dremel. See diagram:

    9) Once removed, separate the stock exhaust from the flex pipe, and pull the remaining parts from the rubber hangers, and pull the whole exhaust system out.
    10) Carefully remove the steel flange gasket from the stock system.

    Aftermarket system replacement (used magnaflow as an example:)
    Attach the "home-run" straight pipe to the rubber hangers, and then join it to the flex pipe flange with new hardware (I chose to use 4 stainless washers, two stainless bolts, and two stainless nuts to re-assemble the new system to the flex pipe flange). While assembling, line up the stock exhaust gasket between the two flanges. Hand tighten the fasteners, we don't need to crank them down yet.
    Attach the aftermarket muffler to the "home run" pipe. Don't worry about the U-Bolts yet. Once attached, hang the new muffler from the rubber hanger(s) that it is set up to attach to.
    Attach the aftermarket tailpipe to the tubing coming from the muffler. Also attach any of the rubber hangers that it's meant to hook up to.
    Install the U-bolts over the two joints where you slid the exhaust together, but don't tighten them.
    Tighten the Flange bolts you installed.
    Make sure the tailpipe and exhaust system are fitted the way you want. You can slide exhaust pieces around a bit to make the tailpipe longer or shorter according to preference. Once you have the fitment you want, tighten the U-bolts.

    You should be all set! Lower the car, and fire her up!

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