Dual Exhaust question

[roparsons]

Hi, I have a 1975 Bronco with a 302. I was recently told I should look at dual exhaust system to help it run better. Any suggestions for a set-up that bolts in with little or no modification needed? Thanks!

 

[DirtDonk]

First, what does “run better“ mean in this case?
What were they trying to tell you? That you could get more power? Or that it would run smoother, quieter, cooler, or something else?
How does it run now?

Up until recently, there really weren’t any bolt on choices. But now there are a couple of them out there that have pretty good reviews here. So some members that have tried the Duff or any other brands can fill in the details. And whether or not you can run them with the stock exhaust manifolds, or if you have to use their headers.
Very likely they have an option for either, but I haven’t checked into it lately.
I think most still have a custom set up, made at the local exhaust shop. But at least now you have options.

Just make sure you’re aware of the limitations of dual exhaust and Broncos.
Never run them straight out the back, and if you have the chance, run both tubes out the passenger side.
Available space is very unavailable on the driver side.

 

[Chicago71Bronco]

Never run them straight out the back, and if you have the chance, run both tubes out the passenger side.
Available space is very unavailable on the driver side.

Sorry to hijack, but why never run them straight out the back?


Sent from my iPhone using Tapatalk

 

[Oldtimer]

Not a hijack.
If run straight out back, air flow sucks exhaust back into vehicle, around and over the tailgate.
Actually if they exit far enough back (like 4-5 inches beyond bumper) exhaust is not an issue, just burned shins.

 

[DirtDonk]

And as porous as most Broncos are, you don’t even have to have the liftgate open, or the top off.
In fact, sometimes it’s better with the top off that on! Lots of little cracks, crevices and holes for the fumes to come in through.

 

[SeaVee]

We’re gonna do a dual into one larger pipe and rout it out the stock location. Local shop.

 

[Broncobowsher]

Sounds like an old timer was giving you some generic old school advise. Most of us have moved on and use a single properly sized exhaust. Has the flow and packages better.
The original location is a well engineered location. Out the side, behind the rear tire. Other locations are more likely to get exhaust in the turbulence that will put it back into the cabin. The old timers will call it the "station wagon effect".

 

[Brush Hog]

After 6 years of fighting to work around a dual exhaust I recently installed 2 into 1 on a mild 302 with 4 barrel carb. Best upgrade ever. More room, less heat, better torque, stays tuned better.

 

[Speedrdr]

Don’t know if it matters whether it’s headers or not. I ran headers on my previous EB and turned a 90* pipe and exited in front of the rear wheels. Full cab, half cab, no cab ——— didn’t notice any exhaust smell. Sitting still, 4 wheel low range in a mud hole, on pavement at speed — — — no exhaust smell.
Limited the amount of heat in the back when running a full top.
Just my experience…

Randy

 

[Lawndart]

I have dual exhaust/headers on mine - been that way for over 100k. Several years back, I had it all redone at a local shop. Nice, clean with cross-over and exits behind the rear wheels. Nice --separated-- rumble at idle - as intended

 

[pcf_mark]

I had true dual exhaust and it was difficult to route the driver's side. It worked fine just looks like crap because I had dip down and around the t-case area. Sounded great had the classic muscle car growl when you got on it. I exited behind the rear wheels pointed ot the side not out the back. This caused the tailpipes to rust out pretty regularly.

Then I went two 2" pipes out of the headers into a single 3" outlet muffler. It sounds different but the packing is much better and it still sounds great.

 

[Shimmy]

i've got a 302 with TBP ss headers into JD dual exhaust. No fitment issues on it and clears everything just fine. It also sounds great. That being said, it does get pretty warm and i'll be doing some heat shielding this summer, especially on the driver side (fuel lines).

 

[Meddle]

Never run them straight out the back,

So NOT how the PO did it on my rig? I’ll admit, it does sound great though!

 

[DirtDonk]

Well, I have to say, in all these years of dealing with Broncos and dual exhaust straight out the back, this is the first time I’ve seen one with wide, flat, rectangular tailpipes!
For all I know, it has the effect of changing the flow characteristics and eliminating fumes in the cabin.
But just like all the rest, only using it will tell. And if it ain’t broke, don’t fix it!

As you’ve already heard in this discussion, there was at least one person who did not have a fume problem. And there have been others too.
But over the years, I’d have to say that 90% of the people who run them either as turn-downs, or as straight out the back, have issues with fumes in the cabin.
For those that angle them out ahead of the tires, it’s probably 50-50.
But 80% of those don’t like the sound.

 

[spap]

I alaways liked how mag g wagone dumped the exhaust out the side, on both sides
but broncos are too short and it would probably get ripped off by a rock pretty quickl y

 

[Chicago71Bronco]

Thanks for the responses about dumping the exhaust straight out the back. That's how mine's set up now (I moved it there from the stock location in my younger days). No wonder I "smell like Bronco" according to my wife.

 

[White Knight]

MagnaFlow has a dual kit for broncos. I have it installed and LOVE it! All stainless from header back and sounds awesome!

 

[56f100bbw]

MagnaFlow has a dual kit for broncos. I have it installed and LOVE it! All stainless from header back and sounds awesome!

Do you have any pictures of it? I’m thinking about doing something like that or I could go single

 

[DirtDonk]

We need pictures!

 

[White Knight]

I tried to get some but have old iPhone… so now that I look at it… not quite “bolt on”