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460 swap into a 78 Bronco

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ArdWrknTrk

Re: 460 swap into a 78 Bronco

Administrator

How loud do you want it?

I have a giant school bus muffler with dual 2 1/2 in and 3" out.

I think it's from a 1975 international 455.
I wish they still made it.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: 460 swap into a 78 Bronco

Administrator

In reply to this post by viven44

I don't know if the Magnaflows are directional. I'd call them and ask.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

ArdWrknTrk

Re: 460 swap into a 78 Bronco

Administrator

In reply to this post by ArdWrknTrk

Bear River has a good selection of mufflers, converters and fittings.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

viven44

Re: 460 swap into a 78 Bronco

In reply to this post by Gary Lewis

Good point, i'll do so.

Vivek

- 'Big Blue 2WD' - 1984 F350 RWD 460/C6
- 1978 Bronco with the heart of a 1986 F250 Bullnose - under restoration
- "Bonded Bronco" -1985 Bronco - 302 4-speed fuel injected, Hibernating future project

viven44

Re: 460 swap into a 78 Bronco

In reply to this post by ArdWrknTrk

I want something with sound resembling new factory Truck/SUV sound. Wife would prefer driving it that way.

viven44

Re: 460 swap into a 78 Bronco

In reply to this post by ArdWrknTrk

Hey look what I found when I searched for dual inlet single outlet mufflers! Something like this Walker 22822 is exactly what I was looking for.

https://www.ford-trucks.com/forums/1219369-dual-inlet-single-outlet-muffler.html

I am also planning to weld a flange so its easy to install and uninstall for maintenance.

Gary Lewis

Re: 460 swap into a 78 Bronco

Administrator

Cool!

Gary, AKA "Gary fellow": Profile

viven44

Re: 460 swap into a 78 Bronco

Well I forgot to state the bad part... that particular muffler has been out of stock for a while.. So i'm still looking

Meanwhile, here is the "muffler" that is on the donor truck. Because this donor truck is all original, something tells me it’s a catalytic converter. Can someone confirm if what I'm looking at is a catalytic converter and not a muffler ? or is the only way to be sure is to send a camera through it and look for honeycombs ?

viven44

Re: 460 swap into a 78 Bronco

In reply to this post by ArdWrknTrk

Is this one similar to the school bus muffler you have ?

https://www.amazon.com/Walker-21533-Quiet-Flow-Stainless-Muffler/dp/B001DR7VTC#customerReviews

ArdWrknTrk

Re: 460 swap into a 78 Bronco

Administrator

In reply to this post by viven44

It's also probably longer than your entire '78 Bronco.

I bought something that would fill the gap between stock head pipes and the sprung hanger on my truck.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

ArdWrknTrk

Re: 460 swap into a 78 Bronco

Administrator

In reply to this post by viven44

That thing has rolled seams, like a can of beans.
The one I bought was 14-15 Ga and has domed ends welded on.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

ArdWrknTrk

Re: 460 swap into a 78 Bronco

Administrator

This one is all welded stainless steel.
It doesn't have rolled edges to rot out.

Dual 2 1/2 in 3" out, 22" long.

https://www.bearriverconverters.store/products/jones-mf2588-muffler-no-stock

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

viven44

Re: 460 swap into a 78 Bronco

Thanks! Looks like a high quality product. Only possible concern I have is that it claims to have a "a deep aggressive sound". I'm after OEM sound (as best as aftermarket can provide).

ArdWrknTrk

Re: 460 swap into a 78 Bronco

Administrator

At a good price.
It's big enough that it shouldn't get loud unless you really get in it. 😉

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

viven44

Re: 460 swap into a 78 Bronco

Wanted to share an area of weakness on the dentsides. There is definitely more metal on these trucks but whatever plastic they used didn’t last as well as the bullnose ones. Maybe why Ford felt comfortable using more plastic on the bullnose as they had made it better.

For instance when I pulled the gauge cluster this is all I recovered !

Fortunately LMC sells the backing plastic for $39 so it was easy to fix

After painting needles with fluorescent paint and adding LEDs we are back in business

I tested the oil pressure gauge, and coolant gauge using the short to ground method. Fuel gauge seems to work. Is there a quick and easy test for the charging gauge (unable to start the vehicle without exhaust currently) ? The wiring is same as a bullnose .. if I plugged in a battery tender type charger would that cause the gauge to go to C ? I’ll probably try tomorrow.

ArdWrknTrk

Re: 460 swap into a 78 Bronco

Administrator

I think the flex circuit is available from a number of vendors, today...

The ammeter is only showing the drop across the shunt.
And the shunt necessarily has to pass all the current that goes into the cab (through the switched & unswitched fuse links.

They never worked well.
That's why CCI converts them to a voltmeter.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: 460 swap into a 78 Bronco

Administrator

In reply to this post by viven44

Looking good, Vivek.

As for testing the ammeter, Jim is right that it just sees the voltage drop across the shunt, which is pretty small. Here's the result of testing I did on 4 different Bullnose ammeters to swing them to full scale in each direction as well as the calculated resistance of the meter itself:

Gary, AKA "Gary fellow": Profile

viven44

Re: 460 swap into a 78 Bronco

This post was updated on .

Thanks Jim and Gary!

I was able to observe functionality this morning but testing the "discharge" side of things. I saw the wiring diagrams for the 78. With the key-off, I noticed the shunt would see current draw if I turned on the Hazard lights, which it did, just did a micro-peg onto the discharge side. On the Bullnose trucks, once should similarly see a peg to discharge side if headlight switch was turned on with the key off. This is a quick and easy way to test the ammeter and see if it works. I found the shunt wire, it is absolutely massive gauge wire. Wonder if it can also support a 3G level current draw??

Fuse Link G is the shunt

On the table below, I don't think i'm following what was done. Was the ammeter out of the truck and did you apply the voltages directly to it? Also why are the voltages 1/100th of the actual voltage ? Is that to keep from frying things ? That makes me think the Shunt is about 100 times lower resistance than the Ammeter itself.

viven44

Re: 460 swap into a 78 Bronco

In reply to this post by ArdWrknTrk

Remarkably the original flex circuit survived as I think it’s made up of Polyimide type material.

What disintegrated is the backing case itself which supports the flex circuit.

Gary Lewis

Re: 460 swap into a 78 Bronco

Administrator

In reply to this post by viven44

I had 4 different ammeters on the bench to test. I hooked my lab power supply up with a DVM measuring voltage and another measuring current. On gauge #1 when the voltage got to .125v in the positive direction the gauge was at full scale and pulling .75 amps. And when I reversed the voltage the gauge was at full scale at .147v and was pulling .88A.

As for the shunt, the largest alternator the Bullnose trucks came with could put out 70A from what I read, although Jim and I've debated this and he's pointed out that there were 100A 1G alternators available. But most of the documentation I have suggests 70A was the max used in the pickups & Broncos and, if so, the shunt was probably sized for that.

I probably have an intact shunt around here some place and ought to run a test some day to see how hot it gets at various amounts of current and we'd know - for that one shunt. But my here's some math: P = I * V so let's assume the shunt is sized such that it'll drop .132v (the average of my 8 full-scale readings) @ 70A and you have 9.27 watts. So if you put in a 130A 3G alternator you'll see 18 watts in a piece of wire maybe a foot long?

Gary, AKA "Gary fellow": Profile

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