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Installing James Duff exhaust system

JAFO

Bronco Guru
Joined
Dec 3, 2007
Messages
1,556
Loc.
Beaverdam
I have uploaded some photos that might help others doing this install.

Duff ceramic headers
Exhaust2.jpg


Muffler in my kit. The muffler inlet, exit was opposite of the instructions. Note the flow arrow. Instructions state that the middle pipe should be the exit. Not this muffler.
Exhaust5.jpg


The L brackets come bare metal. I painted mine and tapped the frame for 5/16" bolts. Rubber grommet in kit goes between frame and bracket. I used stainless bolts to secure bracket. I screwed up welding the piece on the intermediate pipe and my muffler won't connect to bracket. I need to cut my weld and try again. Should have gotten the muffler in place, then tacked that piece on, then removed pipe and completed weld I think.
UPDATE: Duff emailed me pictures showing that a second L bracket that was in my kit can be used in this location. It fits the grommets better and has holes for both sides of the clamp. You would use the short leg containing the large hole for the grommets and the long leg of the bracket with multiple holes for the pipe clamp. I will update the picture as soon as I change my installation.
Exhaust6.jpg


UPDATE: I will be changing to a different L bracket that came in the exhaust kit. I will update pictures as soon as I get this corrected.

I think I mounted them 18.5" from the front side of the rear cross member to the center of the bolt. Trying to figure out the correct length for the driver's side intermediate pipe before cutting and welding on the piece that bolts to the header. This time I will get the muffler in place first, then tack weld that end piece.
Exhaust10.jpg


Passenger side intermediate pipe with header end welded on. It's wrong and I need to cut through my weld, change the angle and re-weld. Learning as I go. Note that the longer intermediate pipe goes on the driver's side and shorter on the passenger side.
Exhaust13.jpg


Note the driver's side header is shorter than passenger side.
Exhaust18.jpg
 
Last edited:

Monster Mike

Sponsor/Vendor
Bronco Guru
Joined
Dec 29, 2010
Messages
1,768
Great Write up!

Im looking into the install instructions, pm's you sent me and the emails as well. trying to balance running the fab/production department by day and moonlight as the parts consultant/ tech guy lol

Cherry Bomb was selling us a muffler we thought was non directional. I will look into that as well.
 

badmuttstang

redneck grease monkey
Joined
Oct 25, 2009
Messages
2,807
The cherry bomb muffler can be run either way they do have a suggested direction for optimum sound but they are non directional.
 

bronconut73

Bronco Guru
Joined
Aug 7, 2012
Messages
9,918
Great Write up!

Im looking into the install instructions, pm's you sent me and the emails as well. trying to balance running the fab/production department by day and moonlight as the parts consultant/ tech guy lol

Cherry Bomb was selling us a muffler we thought was non directional. I will look into that as well.

Mike,

Is that the Vortex or the turbo type?
 

badmuttstang

redneck grease monkey
Joined
Oct 25, 2009
Messages
2,807
Just an edit I just noticed the mufflers you have are the chambered ones they can not be mounted either direction the kit was supposed to come with vortex mufflers which are not chambered and therefore non directional. This will change the exhaust note so I would contact Duff's and tell them about this especially if you where not looking for an exhaust note sounding like flowmaster. They should be able to send you out the correct ones as Cherry bomb probably put the wrong mufflers in their kits.
 

bronconut73

Bronco Guru
Joined
Aug 7, 2012
Messages
9,918
Cherry Bomb sells a chambered muffler like Flow master....
But they drone like a Flowmaster 40 and 44.
Delta Flow Flowmaster's sound great and don't drone on the highway.
 
OP
OP
JAFO

JAFO

Bronco Guru
Joined
Dec 3, 2007
Messages
1,556
Loc.
Beaverdam
Well, I am wanting a good sounding muffler that is not loud on the highway.
I'm not into loud. Maybe I can touch base with monster mike again and sort all this out. This is my first Bronco build and I want it spot on. I'm out of town tomorrow but will email Duff (mike) Sunday. Thanks for all the help everyone.
 

bronconut73

Bronco Guru
Joined
Aug 7, 2012
Messages
9,918
Well, I am wanting a good sounding muffler that is not loud on the highway.
I'm not into loud. Maybe I can touch base with monster mike again and sort all this out. This is my first Bronco build and I want it spot on. I'm out of town tomorrow but will email Duff (mike) Sunday. Thanks for all the help everyone.

Cherry Bomb Vortex sounds great and doesn't drone on the highway....
 
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