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favorite off the shelf exhaust package?

rockinrich

Contributor
Jr. Member
Joined
May 27, 2010
Messages
233
This kit rocks. I installed it with Flowmasters a couple months ago. Easy breezy.

Hello,i am going to get duff's long tube headers as well as their dual exhaust setup but the headers are on backorder for a bit and everything is going to be shipped together but i guess with duals the worry is keeping heat away from the gas lines and i guess thats why alot of guys go with 2 into 1's.May i ask did you move your fuel lines up on top of the frame rail and is it more trouble than it's worth? Just a bit concerned,thanks!
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
47,275
Some have tucked their fuel lines up top, but I believe that most of them were re-doing the lines anyway at the time. Or they had the body off for a larger restoration sometimes too.
It's not that you can't do it when it's all together of course. Just more hassle, like you were thinking.

But if your lines are old, then whether you go with stock routing or re-route them to your tastes you should be considering doing it now no matter what.

And before there is any exhaust on that side at all is the time to do it! Once it's installed, any work you do on that side is nowhere near as much fun.
And don't forget the brake lines and electrical wiring in your scenario.

Paul
 

rockinrich

Contributor
Jr. Member
Joined
May 27, 2010
Messages
233
Some have tucked their fuel lines up top, but I believe that most of them were re-doing the lines anyway at the time. Or they had the body off for a larger restoration sometimes too.
It's not that you can't do it when it's all together of course. Just more hassle, like you were thinking.

But if your lines are old, then whether you go with stock routing or re-route them to your tastes you should be considering doing it now no matter what.

And before there is any exhaust on that side at all is the time to do it! Once it's installed, any work you do on that side is nowhere near as much fun.
And don't forget the brake lines and electrical wiring in your scenario.

Paul
Thanks paul,i appreciate your insight on this and they are probably as old as the truck so now would probably be a great time to put new lines in,good call!
 

Monster Mike

Sponsor/Vendor
Bronco Guru
Joined
Dec 29, 2010
Messages
1,768
Hey everyone! Thank you for your patience on our new 2-1 exhaust kit. There have been several unforeseen setbacks in my personal life and at work that have forced me to temporarily step away from launching this kit.

I am working hard to get back on track and get it done.
 

rudygf@gmail.co

New Member
Joined
Oct 10, 2018
Messages
15
Loc.
Houston
I paid $575 at a local muffler shop and I think it sounds pretty good, not too quiet, not too loud. In total it was $750 because I bought my Borla 40659 mufflers on Amazon for about $90 a piece. The installation was 2 inch in the front due to the limited space between the chassis, transfer case, and crossmember. After the mufflers it is 2 1/4, widened out to 2.5 inch at the tips. I have ceramic hedman elite headers from JEGS and a 347 Stroker from Blueprint Engines. I was concerned it was going to be too loud with Flowmasters, but I'm really happy with these Borlas.

https://www.amazon.com/gp/product/B000CIIAMA/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
 

rockinrich

Contributor
Jr. Member
Joined
May 27, 2010
Messages
233
Hey everyone! Thank you for your patience on our new 2-1 exhaust kit. There have been several unforeseen setbacks in my personal life and at work that have forced me to temporarily step away from launching this kit.

I am working hard to get back on track and get it done.

sorry to hear that mike hang in there bud
 

Monster Mike

Sponsor/Vendor
Bronco Guru
Joined
Dec 29, 2010
Messages
1,768
Thanks Rockinrich.

Ok, the first bit of good news about our new 2-1 exhaust kit in awhile.

I am about to ship the first 4 kits out to see how they fit other peoples Broncos. We tested this kit on a 77 EB with a 351W, C4 & Dana 20 with stock motor mounts, stock front axle, 3.5' suspension lift and 2" of body lift. We are going to ship the first 4 kits to people with different setups then what we know already works.

I am very interested in seeing how it fits on a EB with an AOD/4R70W, NV3550 or AX15.

I am also hoping someone with an Atlas or NP205 transfer case buys one as well. The NP205 and atlas transfer case is one of the primary motivating factors for us to develop a 2-1 exhaust kit since our dual exhaust kit will not work with those transfer cases.

One of the main reasons I shelved this kit earlier this year was after I designed it I had my doubts it would work with the Advance Adapters NV3550/AX15 crossmember. So back to the drawing board and now it should be more versatile. we shall see.

If you are in the market for a 2-1 exhaust kit here are some of the parameters I have to sell it within.
-does not work with any long tube headers
-If you have a 351W the two rear primaries of the PS shorty Drake header will most likely make contact with your inner fender. It makes contact on our 77. See pic below
-only tested with drake shorty headers(EB specific) so far which are sold by most EB vendors as well as Drake direct and Cj pony parts
- at this time the 2-1 kit works with just the Drake shorty headers but we are looking at how it fits with EB specific JBA shorties. The designs are very similar to Drakes. Over time we can look at other shorties too.
-We believe this kit can work with stock non emission EB exhaust manifolds but won't know till next month
-head pipes and merge pipe is 2.25" then mid pipe and tail pipe is 2.5"
-if you want to run our 2-1 exhaust kit and need headers you can buy both from us for as little as $560 and it all ships in a 41x27x7 box(big shipping savings)
-these 2-1 exhaust kits will price out between $319-$399 depending on which muffler you want.
-current muffler options are Flowmaster Delta 44, Magnaflow, Cherry Bomb Pro and Jones Full Boar(first time offering Jones brand)
-headers are $239 for black and $299 for stainless and essentially ship for free but only if you buy the 2-1 exhaust kit at the same time and the shipping is only free if we have the headers in stock.(we plan on keeping them in stock but we don't have any control over that)
-headers use a ball flange to seal the collector to the adapter and adapters have O2 bungs already installed.
-we do not currently offer a shorty header with ceramic coating.
-we plan on offering the 2-1 exhaust kit in stainless with all stainless clamps and muffler but it will be closer to $600 retail. Don't expect the stainless version out till 2019
-we also plan on offering a hardware kit for guys who want to weld the kit together if there is a demand for it.

That about covers most details. if you're interested in being one of the first to try this kit Please Email me at monstermikeduff@gmail.com There are a few people already in line but I am looking for a particular combination of the drive train and other things. In the subject line please type your first and last name then JAMES DUFF 2-1 EXHAUST KIT.

In the email please list off a few things so I can quickly decide if you are a good candidate for the first 4 kits we are sending out and so I can keep track of your specs.


- engine
- engine mounts
- what headers/manifolds you're currently running and do you plan on keeping them?
- transmission
- transmission crossmember
- transfer case
- front axle
- body lift
- suspension lift
- rear inboard shocks yes/no
- rear 4 link yes/no
- what rear gas tank
- what rear bump stops

Thank again everyone for your patience. I am excited to make this a reality!

*NOTE* In the pics below I did not stage the stainless version of the shorties for you to visualize. I will get pics of that later this week or early next week. Bug me about it if I forget.



MM
 

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Monster Mike

Sponsor/Vendor
Bronco Guru
Joined
Dec 29, 2010
Messages
1,768
Nothing like a deadline to get the creative juices flowing...more on that later. For now I have some updates that I wasn't planning on having available this soon.

I made adapter pipes so if you already have the Drake shorty headers or would like to buy them, you can install our dual exhaust kit with them as well as our 2-1 kit. Keep in mind several Bronco vendors sell this header and most companies that sell them just say its their's. Nothing wrong with that but you may think you have a vendors in house brand or a header built to their specs when in fact it's made by Drake. Unless the Shorty header specifically says, Headman, JBA, Sandreson etc.. you may have Drake headers.

I also made a version of our 2-1 kit that works with stock Bronco exhaust manifolds (non emission style). It is a little more labor intensive so expect it to cost more. This kit will not be offered in stainless, just aluminized. The 2-1 that we are making for the shorty headers will be offered in stainless after the holidays (early 2019)

One thing we are concerned with about our 2-1 exhaust kit is how it will work with a suspension lift under 2". I'll be doing more testing on that soon & let everyone know.

If you are running a high pinion front axle that is stock width for an EB, you will make contact with the front driveshaft and the drivers side head pipe from stock height to 6" of lift. If you are running a full width high pinion front axle it may not be an issue since the pinion would be offset 3 inches further to the driver side. The reason for this potential clearance issue is the driver side head pipe snakes around to the passenger side right above the front driveline. We have tested it on a 3.5" long arm lift with a 351 windsor, stock motor mounts & stock front axle. It passed the articulation test with ease.

Having these options I listed above will give more Bronco's the opportunity to run an off the shelf exhaust kit.

In fact there are some out there that run full width high pinion front axles and can't use our long tube headers due to driveshaft interference. Now we have a shorty header that I hope will work on full width high pinion axles with both of our off the shelf exhaust systems. Again, those combinations have not been tested so it's just an educated guess at this point.

As we continue forward we will do more testing and adapting and report back.

MM
 
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Bronco744me

New Member
Joined
Aug 16, 2013
Messages
18
Loc.
Hartselle,Al
Mike,
I just installed one of your kits on my 74-3 speed manual with TBP long tube headers,cheery bomb vortex and I thought it was a relatively easy exhaust system to install I did have to do a little adjusting on the intermediate pipes and their brackets as far as where the brackets fell on the frame so that the exhaust pipes would sit a little farther back from the rear wheels but all in all great kit for a diy,really like dealing with duff's excellent customer service.Thanks again,Edd
 

Monster Mike

Sponsor/Vendor
Bronco Guru
Joined
Dec 29, 2010
Messages
1,768
Mike,
I just installed one of your kits on my 74-3 speed manual with TBP long tube headers,cheery bomb vortex and I thought it was a relatively easy exhaust system to install I did have to do a little adjusting on the intermediate pipes and their brackets as far as where the brackets fell on the frame so that the exhaust pipes would sit a little farther back from the rear wheels but all in all great kit for a diy,really like dealing with duff's excellent customer service.Thanks again,Edd


Edd, Thanks for the feedback and all of us here appreciate the kind words. We really like giving customers a product that they can install at their home. It's always a great feeling when you can DIY. :cool:
 

Monster Mike

Sponsor/Vendor
Bronco Guru
Joined
Dec 29, 2010
Messages
1,768
I have the first two 2-1 kits shipped out to members that are going to give me their feedback on how the kit fits on their Bronco.

Their Broncos are setup different then ours so it will be great to knock a couple more combinations off the list or at the worst fix a problem we didn't see on our Bronco's.

I am actively looking for 4 more candidates that can help me with test fitment.

The first candidate must have an AX15 or NV3550 and is using the crossmember made by Advance Adapters. If you are running that transmission and are not sure which crossmember you have you can email me pictures.

The second one needs to have a ZF 5 speed

The third candidate needs to have a 351W with stock 302/289 EB manifolds. I honestly don't know if this is an odd combination but I know it exists

Fourth has to have a 289/302/5.0 with stock EB manifolds

Please copy and paste this list below to the email you send me and fill it out so I can let you know if you qualify.
monstermikeduff@gmail.com

- engine
- engine mounts
- what headers/manifolds you're currently running and do you plan on keeping them?
- transmission
- transmission crossmember
- transfer case
- front axle
- body lift
- suspension lift
- rear inboard shocks yes/no
- rear 4 link yes/no
- what rear gas tank
- what rear bump stops

sorry for some of the pics rotated the wrong way. No matter what I try they won't cooperate. Please scroll up for some other pics and tech I already posted.

MM
 

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BigB

Sr. Member
Joined
Nov 19, 2011
Messages
395
I have the first two 2-1 kits shipped out to members that are going to give me their feedback on how the kit fits on their Bronco.

Their Broncos are setup different then ours so it will be great to knock a couple more combinations off the list or at the worst fix a problem we didn't see on our Bronco's.

I am actively looking for 4 more candidates that can help me with test fitment.

The first candidate must have an AX15 or NV3550 and is using the crossmember made by Advance Adapters. If you are running that transmission and are not sure which crossmember you have you can email me pictures.

The second one needs to have a ZF 5 speed

The third candidate needs to have a 351W with stock 302/289 EB manifolds. I honestly don't know if this is an odd combination but I know it exists

Fourth has to have a 289/302/5.0 with stock EB manifolds

Please copy and paste this list below to the email you send me and fill it out so I can let you know if you qualify.
monstermikeduff@gmail.com

- engine
- engine mounts
- what headers/manifolds you're currently running and do you plan on keeping them?
- transmission
- transmission crossmember
- transfer case
- front axle
- body lift
- suspension lift
- rear inboard shocks yes/no
- rear 4 link yes/no
- what rear gas tank
- what rear bump stops

sorry for some of the pics rotated the wrong way. No matter what I try they won't cooperate. Please scroll up for some other pics and tech I already posted.

MM

Hi Mike,

What's the performance of your system going into 1 pipe well before the muffler as opposed to a regular 2 into 1 of which both pipes enter the muffler?

Thanks.
 

Monster Mike

Sponsor/Vendor
Bronco Guru
Joined
Dec 29, 2010
Messages
1,768
Hi Mike,

What's the performance of your system going into 1 pipe well before the muffler as opposed to a regular 2 into 1 of which both pipes enter the muffler?

Thanks.

I don't have dyno specs. All I can tell you is my seat of the pants experience driving the Bronco. I felt no difference between the 2. Our original design had 2 pipes going into the muffler. We tested it for several months then changed it to the current setup. Now The 2 pipes merge into a larger pipe before entering the muffler.

By changing the design we are hoping to offer this kit to broncos with the AX15 & NV3550 as well as Broncos with stock exhaust manifolds.

At the time when I originally started designing the exhaust kit I was working with a stock configured drive train. I felt it would have been a large oversight on my part to not have this kit work with more aftermarket transmissions and their crossmembers.

MM
 
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BigB

Sr. Member
Joined
Nov 19, 2011
Messages
395
I don't have dyno specs. All I can tell you is my seat of the pants experience driving the Bronco. I felt no difference between the 2. Our original design had 2 pipes going into the muffler. We tested it for several months then changed it to the current setup. Now The 2 pipes merge into a larger pipe before entering the muffler.

By changing the design we are hoping to offer this kit to broncos with the AX15 & NV3550 as well as Broncos with stock exhaust manifolds.

At the time when I originally started designing the exhaust kit I was working with a stock drive train. I felt it would have been a large oversight on my part to not have this kit work with more aftermarket transmissions and their crossmembers.

MM

Thanks mate.
 

Monster Mike

Sponsor/Vendor
Bronco Guru
Joined
Dec 29, 2010
Messages
1,768
A few more updates on the 2-1 exhaust kit.

I gotta be honest, this kit and all the options it has is starting to get me pretty excited.

Which brings me to my next thought...

Black Friday is coming :cool:

Check out all the info and updates here

http://classicbroncos.com/forums/showthread.php?t=290733

Make sure to check out dufftuff.com while you're stuffing your face with turkey ;D
 

Monster Mike

Sponsor/Vendor
Bronco Guru
Joined
Dec 29, 2010
Messages
1,768
Hey Mike so if we haven’t gotten a reply does that mean we didn’t qualify?

It more likely means

A. I never opened your email and then it got buried or
B. I opened it then got busy and forgot to get back to you

Please send the email again and make sure it is going to

monstermikeduff@gmail.com

I'll check my spam too.

Thanks!
 
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