FJ60/62 Aftermarket Exhaust - More Theorycraft

[SteveH]

My exhaust shop did 2.5" from the cat back, with a turbo muffler (a reputable brand - but not Flowmaster or Flo-pro).

He said that if you have cats, you can get away with a turbo muffler, but if you delete the cat and install a turbo muffler, you will get droning. Another shop verified this years ago. So, my FJ62 has a slightly-louder-than-stock sound outside the truck, but no annoying drone inside on the highway. This shop bent the tailpipe to come out behind the driver's side mudflap and used all factory connection points up to there. I'm very happy with the noise/performance of this system. Any system should be capable of being lowered enough to service the driver's side rear spring shackle - so beware that.

 

[gregnash]

My exhaust shop did 2.5" from the cat back, with a turbo muffler (a reputable brand - but not Flowmaster or Flo-pro).

He said that if you have cats, you can get away with a turbo muffler, but if you delete the cat and install a turbo muffler, you will get droning. Another shop verified this years ago. So, my FJ62 has a slightly-louder-than-stock sound outside the truck, but no annoying drone inside on the highway. This shop bent the tailpipe to come out behind the driver's side mudflap and used all factory connection points up to there. I'm very happy with the noise/performance of this system. Any system should be capable of being lowered enough to service the driver's side rear spring shackle - so beware that.

Yup... that last part is why I plan to build that tailpipe section in a couple of sections, so that should I need to work in that area again I can "easily" remove the tailpipe and not have issues with interference. I am hoping to use all the stock mounting locations but we will see. I just got the muffler yesterday to find out that the coupler I had purchased to adapt the 2" to 2.5" was actually an ID to OD (OD being 2.5 section) so I cannot mount as easily as I had planned. Contacted the company and they are working with me as it states ID/ID on the sticker and selling post. I sent them "feedback" to let them know as the couple was $7 shipped so didn't expect them to really do anything, but they want some pictures and then are willing to work with me. so that is definitely cool.

 

[gregnash]

Ok figured I probably should update my own thread that I started...
Here is what I ended up purchasing....
- 2"ID to 2.5"ID Coupler ($7 on ebay)
- 2.25" Coupler (used to attach 2.5" coupler to 2" stock pipe.... $3 at O'Reilly)
- 2 2.25" u-bolt clamps to hold coupler ends, this will be permanent until I can replace all the system with 2.5" piping ($3ea at OReilly)
- Mild steel 2.5" ID flange to 2.5" end of coupler ($15ea two pair needed, set of inlet and set for outlet, from Amazon prime shipped)
- Mild steel 2.5" ID flange to 2.5" inlet and outlet of Thrush Welded Muffler ($37 from Amazon prime shipped)
- 45* 2.5" exhaust elbow 12" long ($7 from OReilly, had to buy 3 as messed one up) going from muffler outlet flange pointing up to go over axle
- 45* 2.5" exhaust elbow 12" long connected to first to point down over axle
- 24" section of 2.5" exhaust straight pipe ($9 from OReilly) connected to elbow and pointed in-between spring and frame (will need to come up with custom angle to connect elbow and straight to get angle correct), ended up cutting about 8" off for my fitment
- 12" section of 2.5" dump pipe/turn down for termination behind rear wheel at fender ($7 at OReilly)
- 3 2.5" u-bolt clamps to hold things for the time being while I figure out the remainder of welds ($4ea)

So that brings me to a grand total of...... $132 with me messing up one 45* elbow but it should still be salvageable for the custom turn I need, if not I have plenty of scrap pipe left over. Also, I am sure that I could have paid less for some things but I went with what was local and accessible. One thing I don't like is that the pipe you purchase from your LAPS is not mandrel bent, so you get the ripples in the steel, which does not look clean to me. Also, the steel is aluminized so you have to clean the coating off before you weld, which is just extra time. All in all I have spent maybe 8hrs messing with it, got everything together the way I need just have to get that small custom bend welded up and then I am good to go. I checked with a couple of local muffler shops around town and cheapest I was quote for similar was $275-$300 and at least a full days work. So pretty significant savings if you are creative and have a welder.

IMG_3087 by Greg Fisicaro, on Flickr
IMG_3088 by Greg Fisicaro, on Flickr

IMG_3090 by Greg Fisicaro, on Flickr
IMG_3089 by Greg Fisicaro, on Flickr
IMG_3091 by Greg Fisicaro, on Flickr

And here is a little video of they system running at current state with pipe dumping like pic above.. I do have to say that it was a bit drone-y on the highway when I first start driving it but now it has broken in some and getting more mild.