Ferdinand - '85 Bronco 351W XLT "Phoenix" rebuild project...

[Gary Lewis]

No, sorry, I don't.  But it was a single inlet/dual outlet one since that's the style of Flowmaster that was on Rusty.  And it was about 24" long.  Hope that helps.

[Steve83]

This is the closest to original SS made in USA:



I couldn't find a stainless tailpipe (even from the same mfr., who offers SS tailpipes, and Bronco tailpipes, but refused to make me a SS Bronco tailpipe), so I made one.

[Ferdinand]

Holy cow Steve that set up looks great!

[Ferdinand]

Thanks Gary. I ordered a kit from Jegs. I am going to get everything mocked up and then see what kind of room I have for the mufflers and what outlet configuration I need. I did settle in on the Magnaflows

[Ferdinand]

01.25.19 Update

I made an appointment for a front end alignment tomorrow afternoon. So, I ran down to the local gas station to fill up and when I went to start it back up, smoke was rolling out from under the hood...  (Talk about Deja Vu!)

Here that ground wire I put on the alternator completely melted!! Then I could net get it started again. What a blow to my confidence that this thing was wrapping up.

I'll try to have some pictures loaded tomorrow with some more narrative. Losing steam. Getting stranded out in 26 degree weather with stiff wind was no fun. 🙃

[Steve83]

Ferdinand wrote

...I went to start it back up, smoke was rolling out from under the hood.

Did the smoke ONLY appear during cranking?  Or did it look like it had been smoking for a while, and just blew out where you could see it when the fan started spinning?

The first thing that suggests is a poor block ground.

[Gary Lewis]

Bummer!  That does tend to destroy confidence.  But Steve's suggestion/question is a good one - block ground.

Anyway, sorry for the problem, but it is just another ring of onion for the Bloomin' Onion you are creating for a celebration.  

[Ferdinand]

So I checked my block ground and it is still in good shape. I ran 4 gauge wire from the battery to the frame, and the same size wire from the frame to the block. All good there so I am not sure what to look for next. I checked the status of the exhaust kit I ordered and it is on backorder with no estimate on ship date. Since I am trying to get this inspected within the next 2 weeks, I am going to try and make a template for what I need and have someone weld it up for me.

Progress tonight:

My jig for an extra set of hands:






If anyone sees anything routed poorly or has another suggestion for a route, I am all ears.

I plan to work on the muffler section tomorrow evening. I would like to mount the mufflers as far to the rear as I can to keep resonance down. I am still trying to decide where to exit. I don't mind before the rear wheel, but the longer route up over the rear axle is what I would prefer.

This is the exit I most want, but am not real sure if I will have room:

[Ferdinand]

I really think it was smoking when I pulled in but I never noticed it while the guy was pumping the gas. (we are still SO fortunate to have an old fashioned full-service station in town) and while I was chatting with him, my line of sight was in the direction of the hood. It was pretty windy last night though.

But as soon as I turned the key is when I really noticed it.

[Ferdinand]

Steve, would you recommend these round style mufflers over the oval style? I am trying to lay out some templates for piping and I only have the two runs spaced at 1.5" at the moment. The round mufflers would probably require more clearance. However, if I could I could try to stagger them in line. Thoughts?

[Gary Lewis]

I know you asked Steve, but I'll comment as well on the muffs.  Magnaflow makes a dual-inlet/dual-outlet muff that might work for you if space is tight.  But you might be able to run oval muffs vertically to get clearance.

Anyway, that's cool the way you've run the exhaust using PVC pipe.  That's ingenious.  

On the smoking, you haven't found burned wires?  Can't see smoke while idling w/the hood up?  Perhaps you have a valve cover leak or the sending unit is leaking and hitting the exhaust?

[Gary Lewis]

Oh yes, I think most exhausts run the driver's side to the passenger side up ahead of the transmission.  And if you could do that you'd have more room for muffs toward the rear as you wouldn't have the 90 right there by the transmission's crossmember.

[Ferdinand]

Thanks Gary. You use what you know and since I am no welder and was a home builder for years PVC was an easy go-to for a template

I did see the dual inlet/outlet, and the Ovals mounted vertically. I had planned to mount ovals vertically since that was the design of the MF mufflers I was reading up on.

As far as the wiring. Yes, The isolated ground that I ran a few days back from the alternator to the ground side of the solenoid was melted the entire length.

[Rembrant]

Ferdinand wrote

I did see the dual inlet/outlet, and the Ovals mounted vertically. I had planned to mount ovals vertically since that was the design of the MF mufflers I was reading up on.

Hey Ferdinand,

Not sure if this is any help with your design or not, but here is what I'm running for Magnaflows on my 1984 short wheel base. (How much shorter is the Bronco, anyway?). Note: I'm running a 302, and my duals are 2.25" all the way through.



https://www.magnaflow.com/products?partNumber=11235

The same muffler but for 2.5" pipe would be the Magnaflow 11236.

I'm running BBK shorty headers, so up front the duals were run pretty much in the stock location as the stock Y-pipe. Mufflers were mounted vertically with the offset bottom inlet and offset top outlet. Stock hangers were re-used.






My exhaust was installed with the spare tire mounted under the frame in the stock location, so the pipes had to leave enough room for me to not lose that mounting.

I was trying to follow Lariat85's truck as a basic template for my tailpipe exits. I wanted the angled tailpipe sticking out behind each rear wheel, but short and tight to the body. Just like in the picture of his truck below (which I printed and took to the Muffler shop with me...lol...thanks Lariat85!). Mine is a Flareside of course, so the exists aren't quite identical as his, but his tailpipes very clean and tidy looking in my opinion.

[Gary Lewis]

Ferdinand - I'd forgotten about that ground burning.    But with it melted you obviously had way too much current through it.  How big is it?

That suggests that the fender isn't getting grounded the usual way.  With the exception of the diesel trucks which had two extra grounds going to the RH fender, it appears the whole body arrangement was supposed to ground via the single ground from the engine to the firewall.  (You do have that one, right?)

In other words, all of the fasteners holding the fenders to the cab, and the radiator support to the fenders were supposed to be the electrical path.  But if those fasteners and body parts have been painted then there's a good (bad?) chance that the ground path will be poor.

If it were me I'd take that burned ground off and check voltage drops from the battery's negative post to the radiator support, fenders, and cab - with the engine running and lots of accessories turned on.  And then, if the voltage drops are considerable as I expect them to be, I'd put ground wires to several places.

Rembrant - Those pics are awesome!  I like the routing.  How does it sound?

[grumpin]

Hey Ferdinand,

Not sure if this is any help with your design or not, but here is what I'm running for Magnaflows on my 1984 short wheel base. (How much shorter is the Bronco, anyway?). Note: I'm running a 302, and my duals are 2.25" all the way through.




I believe it's 117" compared to 104.7". That's the first thing I wondered when I started driving my Bronco.

They are a bit "squirrely" IMO.

Edit: Rembrant, your exhaust looks good!

[Steve83]

Ferdinand wrote

...round style mufflers over the oval style?

I figure Ford had good reasons for choosing round, and I like the way Ford builds vehicles.  So rather than try to reverse-engineer it or take a chance on something different for no particular reason, I went with the most-durable (SS) version of the factory muffler I could find.

Ferdinand wrote

...I could try to stagger them in line.

I doubt there's enough room in a Bronco.

Ferdinand wrote

The isolated ground that I ran a few days back from the alternator to the ground side of the solenoid was melted the entire length.

Then my next guess is that the alternator case is NOT actually grounded to the block, so all its current has to pass through that extra ground.  I'd unmount it, and any brackets between it & the head/block, and clean EVERY mating surface down to shiny metal.  Then apply electrical grease (NOT dielectric, thermal, anti-seize, conductive, chassis, lithium, or battery snot) and reassemble.

[LARIAT 85]

I am honored, Chief!  

[Ferdinand]

Lariat 85,
Any chance you have any pictures of your exhaust set-up from under the truck?

That tail pipe exit is exactly what I am looking for but am having a bit of difficulty getting my mock up the way I want it...

I would be grateful for any help. You have one sweet ride for sure!

[Ferdinand]

Rembrant,

This is crazy helpful!! Thanks a million‼️

(the mock up is going slow, but I'm trying to stay focused)