James Duff Dual Exhaust Install Question

[neilvonarb]

Anyone else had an issue installing the drivers side muffler with the James Duff dual exhaust kit?

What I have:
- 1974 Bronco pretty much stock underneath (nothing extra or out of place)
- TBP long tube headers (not sure this makes a difference with what my problem is)
- James Duff dual exhaust kit with JD part 3093 (TBP long tube adapters)
- Flowmaster 40 mufflers

What the "problem" is:
- The length of the driver side intermediate pipe that comes with the kit lands the edge of the body of the muffler just beyond the E-brake cable bracket and cables, causing the top of the muffler to hit the cables coming out of the back of the bracket. Instructions in the kit tell you that you may need to cut length off of the intermediate pipe when using Flowmaster mufflers but that would make this situation worse since it would put the body of the muffler right at the bracket, pushing the bottom of the muffler even lower. It can all be installed and be functional, it's just that JD recommends the bottom of the muffler be above or at least flush with the bottom of the leaf spring hanger. Both scenarios - pushing the muffler down so the top doesn't hit the E-brake cables and moving the muffler towards the front of the vehicle - pushes the muffler down below the leaf spring hanger quite a bit. Rotating the muffler would raise the bottom, but JD also states that the mufflers are meant to be installed vertically without being angled.

Thanks for any JD-specific or general exhaust install help.

 

[billh1289]

I don’t have any insight on this since I don’t run that kit, but I believe Nashville bronco did a video using that kit and he had the TBP long tubes. Might be worth a watch to see if you can spot something.

 

[neilvonarb]

Yeah, I've watched the video - it's actually the video JD puts on their website where you buy the kit - but they start on the passenger side and pretty much only show the detail installation of that side. Thanks, though.

 

[billh1289]

Yeah, I've watched the video - it's actually the video JD puts on their website where you buy the kit - but they start on the passenger side and pretty much only show the detail installation of that side. Thanks, though.

Of course it would be the other side. That would be my luck too… someone that has installed this kit will jump in I’m sure.

 

[Monster Mike]

This is a great question and the timing is great too as I just purchased a new to me 72 EB and we installed this exhaust system on it today. The Bronco has a 302 with our old school long tube Duffy Torquer headers, a 4 speed manual and a dana 20. No body lift with an older Duff 3.5 suspension. Stock axles with a 23 gallon BC gas tank. The E brake cables are installed as well.

I gave the kit to our new mechanic who also owns an EB and has built several Bronco's. This was the first time he has installed 1 of our exhaust kits so I decided to walk away on this install and see what he came up with on his own.

It is amazing how many ways you can skin a cat with the same parts and a different Bronco & in this case a different person installing them. He did a great job and the kit went in great. He just did it differently then how we instruct our customers to install it so I am looking forward to putting it to the test. Who knows, maybe we will change our install instructions.

In regards to the driver side pipes and muffler, it is difficult to have everything where you want it with no body lift w/o making a compromise somewhere. You will see in the pic below, our mechanic chose to install the muffler with it touching the ebrake cables. He believes there should not be enough heat generated by the muffler to melt the E brake cable sheath and the rubbing and touching is of no concern as well. Since it is my Bronco I am happy to test these theories. For the rest of you, if this is not a solution you want to consider, then you will have to make a compromise in how you install the system. Keep in mind, this is really only an issue when you do not have a body lift. This is why we didn't address it on the install video or in the install instructions because every flippin Bronco we have played with so far has had a body lift. Thus, the problem didn't present itself. If you plan on installing a body lift anyways, I would consider doing that first then installing the exhaust.

If you do not plan on installing a body lift and you do not plan on running our Torque Tamer you can twist the muffler more diagonally to clear the E-brake.

If you do not plan on doing any hard wheeling or off roading with your Bronco you can also install the whole system lower to clear the E brake cables.

And last due to it being my least popular option, you can rotate the mufller 180 degrees and let it hang even lower. Just keep in mind this May make your tail pipes hang lower too.

All in all, I think this kit fits great & offers a lot of flexibility for all the different ways we can build an EB but sometimes you have to color outside the lines a little to get everything to work together.

Hope that helps and I will try to remember to report back with how it is positioned on my Bronco right now. This Bronco will be testing several of our different exhaust kits and Dyno testing our old headers against our new Dominators as well as going head to head with some other header options on the market.

I would highly recommend subscribing to my youtube channel, Bronco Garage. With 3 new EB's in the stable and a Bronco Mechanic here wrenching full time, we are going to turn the volume up on product installs and testing.

MM

 

[ngsd]

I have done the duff kits and while they are good, I found it was a much better value to find a great muffler shop to do it all.

 

[Shimmy]

definitely don't want any exhaust pipes touching anything at all. that's not acceptable imo

 

[BGBronco]

I have the Duff dual exhaust kit installed with no body lift. I'm close but not touching the ebrake parts.

 

[neilvonarb]

This is a great question and the timing is great too as I just purchased a new to me 72 EB and we installed this exhaust system on it today. The Bronco has a 302 with our old school long tube Duffy Torquer headers, a 4 speed manual and a dana 20. No body lift with an older Duff 3.5 suspension. Stock axles with a 23 gallon BC gas tank. The E brake cables are installed as well.

I gave the kit to our new mechanic who also owns an EB and has built several Bronco's. This was the first time he has installed 1 of our exhaust kits so I decided to walk away on this install and see what he came up with on his own.

It is amazing how many ways you can skin a cat with the same parts and a different Bronco & in this case a different person installing them. He did a great job and the kit went in great. He just did it differently then how we instruct our customers to install it so I am looking forward to putting it to the test. Who knows, maybe we will change our install instructions.

In regards to the driver side pipes and muffler, it is difficult to have everything where you want it with no body lift w/o making a compromise somewhere. You will see in the pic below, our mechanic chose to install the muffler with it touching the ebrake cables. He believes there should not be enough heat generated by the muffler to melt the E brake cable sheath and the rubbing and touching is of no concern as well. Since it is my Bronco I am happy to test these theories. For the rest of you, if this is not a solution you want to consider, then you will have to make a compromise in how you install the system. Keep in mind, this is really only an issue when you do not have a body lift. This is why we didn't address it on the install video or in the install instructions because every flippin Bronco we have played with so far has had a body lift. Thus, the problem didn't present itself. If you plan on installing a body lift anyways, I would consider doing that first then installing the exhaust.

If you do not plan on installing a body lift and you do not plan on running our Torque Tamer you can twist the muffler more diagonally to clear the E-brake.

If you do not plan on doing any hard wheeling or off roading with your Bronco you can also install the whole system lower to clear the E brake cables.

And last due to it being my least popular option, you can rotate the mufller 180 degrees and let it hang even lower. Just keep in mind this May make your tail pipes hang lower too.

All in all, I think this kit fits great & offers a lot of flexibility for all the different ways we can build an EB but sometimes you have to color outside the lines a little to get everything to work together.

Hope that helps and I will try to remember to report back with how it is positioned on my Bronco right now. This Bronco will be testing several of our different exhaust kits and Dyno testing our old headers against our new Dominators as well as going head to head with some other header options on the market.

I would highly recommend subscribing to my youtube channel, Bronco Garage. With 3 new EB's in the stable and a Bronco Mechanic here wrenching full time, we are going to turn the volume up on product installs and testing.

MM

Thanks for the detail response, Mike. I tend to take things in instructions a little too literally sometimes. I’m going to get back under there and see what I can figure out. If you make revisions to the install instructions, one could be having people start on the drivers side. It seems like you want things pretty symmetrical from the muffler back, and with more limitations on the drivers side, starting there doesn’t let you do something on the passengers side that won’t be possible on the drivers side.

 

[neilvonarb]

I have the Duff dual exhaust kit installed with no body lift. I'm close but not touching the ebrake parts. View attachment 883219

Thanks for the pic, BGBronco. This is kind of where I’m at. I have the Flowmaster mufflers which have more of a box shape which make them tighter up by the e-brake cable. Is that the Duff intermediate pipe that came in the kit? The end of yours landed quite bit further back than mine is.

 

[Shimmy]

OP, did you figure your's out? what did you end up doing?

I'm finishing up my install, but opted for the Borla mufflers. due to their compact size, i didn't have any issues and everything went together reasonably well.

 

[neilvonarb]

OP, did you figure your's out? what did you end up doing?

I'm finishing up my install, but opted for the Borla mufflers. due to their compact size, i didn't have any issues and everything went together reasonably well.

I ended up just making it work. On the drivers side, I ended up dropping and rotating the muffler a little to clear the e-brake bracket and work okay between the e-brake cables coming out of the bracket. It would have been nice if the intermediate pipe had been a little longer. It would have pushed the muffler more towards the back which would have gotten it out of the whole e-brake bracket/cable area. I re-worked the passenger side to get it as close to symmetrical as possible.

I will say you have to try to get the last tailpipe strap/bracket that is supposed to mount to the bottom of the frame pretty plumb above the pipe. If it's at an angle, even if you tighten the crap out of everything, it will swing slightly and move the final location of your tailpipes (assuming you have them mocked up where you want them with jack stands).

 

[Shimmy]

I will say you have to try to get the last tailpipe strap/bracket that is supposed to mount to the bottom of the frame pretty plumb above the pipe. If it's at an angle, even if you tighten the crap out of everything, it will swing slightly and move the final location of your tailpipes (assuming you have them mocked up where you want them with jack stands).

Thanks for the update! I know what you mean! i also ended up drilling a new hole in the rubber strap to pull the pipe up more.