Big Blue

[Gary Lewis]

I’ll use the power distribution box as well as the rest of the EEC-V harness...

What EEC-V harness? From some particular donor vehicle, or some aftermarket setup?

...relay that will not parallel the batteries until two minutes after the alternator kicks in. That way a dead or low auxiliary battery won’t drain the main battery when the key is turned to On.

But then if the main is dead, how do you connect the aux? And what if you want the added time of running key-off accessories by using both batteries?

I fear the frame is cracked, if not broken, at the steering sector box as there’s a loud clunk coming from that area on turns.

Have you read the frame noise TSB?

https://www.supermotors.net/registry/2742/54113-2

...true duals will run from there...

I'm not a fan of the noise, or weight, or extra bulk & labor, or inefficiency. The exhaust system is like a wind instrument - it's tuned to the engine (from the factory) to get the pulse from one cylinder to help scavenge more exhaust from the next. The next (in the firing order) might be (and often IS) on the opposite bank; so separating the exhaust prevents that benefit. The proof is that true duals are louder - that energy is being wasted as noise.

Steve - The wiring harness and air inlet system are from a '96 CA-spec F250 w/a 460.

As for connecting the two batteries, I didn't explain that there's an optional that I'll install to force the two batteries into parallel. Not sure where I'll install the switch, but I'll also put a warning light on the dash to show they are paralleled.

And, I had read TSB 97-03-10, although on here instead of SuperMotors.

And while I won't argue about the efficiency issue, I do plan to have dual exhaust. Part of the plan is to use as much of Huck as I can, and one of the things I'll use is its dual exhaust system. However, I won't go back w/the glass packs as I don't like the noise the current glass packs give. Instead I'm going with Magnaflows as I like the low rumble they give. But, to each his own.

[85lebaront2]

And while I won't argue about the efficiency issue, I do plan to have dual exhaust. Part of the plan is to use as much of Huck as I can, and one of the things I'll use is its dual exhaust system. However, I won't go back w/the glass packs as I don't like the noise the current glass packs give. Instead I'm going with Magnaflows as I like the low rumble they give. But, to each his own.

Steve and Gary, Darth's exhaust system is still essentially stock (original muffler and tailpipe) it is dual from the engine to the muffler with a cross pipe where the single O2 sensor on the 1990 parts truck was mounted (it now has my wideband there). This system (which originally had no cross pipe) was a mid 1984 through 1987 system. The 1990 was dual to the catalytic converter inlet (O2 sensor just forward) then a large single from the converter to the muffler and dual tailpipes. The only change I made before the EFI/E4OD change was to remove the screens from the end of the tailpipe at the recommendation of my local exhaust shop, I had asked about a lower restriction muffler and was told I would gain more from that then what he could sell me. the only issue I ever had was pulling the 5th wheel up the on ramp to the interstate before everything was fully warmed up, when I let off the throttle when the road leveled off, my wife reported she saw a rather large flame from the tailpipe which I heard as a loud boom from inside, the Thermactor system ignited the remaining mixture in the exhaust manifolds. He also told me when I drove down to him after doing the EFI conversion and E4OD, to remove the muffler heat shield as it would eventually rust the muffler from the outside. The 1996 bed has heat shields on the bottom as far back as the rear axle location.

 

[Gary Lewis]

And while I won't argue about the efficiency issue, I do plan to have dual exhaust. Part of the plan is to use as much of Huck as I can, and one of the things I'll use is its dual exhaust system. However, I won't go back w/the glass packs as I don't like the noise the current glass packs give. Instead I'm going with Magnaflows as I like the low rumble they give. But, to each his own.

Steve and Gary, Darth's exhaust system is still essentially stock (original muffler and tailpipe) it is dual from the engine to the muffler with a cross pipe where the single O2 sensor on the 1990 parts truck was mounted (it now has my wideband there). This system (which originally had no cross pipe) was a mid 1984 through 1987 system. The 1990 was dual to the catalytic converter inlet (O2 sensor just forward) then a large single from the converter to the muffler and dual tailpipes. The only change I made before the EFI/E4OD change was to remove the screens from the end of the tailpipe at the recommendation of my local exhaust shop, I had asked about a lower restriction muffler and was told I would gain more from that then what he could sell me. the only issue I ever had was pulling the 5th wheel up the on ramp to the interstate before everything was fully warmed up, when I let off the throttle when the road leveled off, my wife reported she saw a rather large flame from the tailpipe which I heard as a loud boom from inside, the Thermactor system ignited the remaining mixture in the exhaust manifolds. He also told me when I drove down to him after doing the EFI conversion and E4OD, to remove the muffler heat shield as it would eventually rust the muffler from the outside. The 1996 bed has heat shields on the bottom as far back as the rear axle location.

Yes, that's essentially the system that I took off Huck and plan to use on Big Blue. But, it has no cats and is dual the whole way. Fortunately the guy that cut the frame also cut the exhaust - right ahead of the mufflers. So I'll use the exhaust pipes as is, and have someone graft on the muffs and tail pipes.

[Steve83]

The 1990 was dual to the catalytic converter inlet (O2 sensor just forward) then a large single from the converter to the muffler and dual tailpipes.

That's how all '87-96 EFI exhausts are built; other than the dual tailpipes on the bigger V8s (& the unique Lightning exhaust).

https://supermotors.net/getfile/933303/thumbnail/exhaustefi.jpg

...the muffler heat shield as it would eventually rust the muffler from the outside.

Mine still haven't. So I don't doubt that a lot of mufflers in your area rust out, but it's not due to the heat shield (which keeps the muffler hotter, and therefore drier).

The 1996 bed has heat shields on the bottom as far back as the rear axle location.

All these trucks that I've seen have body heat shields along nearly the entire Right frame rail. Certainly all '82-96 Broncos are fully-shielded from the firewall-to-floorpan seam (11398), under the passenger seat (114A46), back to the gas tank (112B26):

https://supermotors.net/getfile/1047800/thumbnail/bodysheetmetal.jpg

[85lebaront2]

The 1990 was dual to the catalytic converter inlet (O2 sensor just forward) then a large single from the converter to the muffler and dual tailpipes.

That's how all '87-96 EFI exhausts are built; other than the dual tailpipes on the bigger V8s (& the unique Lightning exhaust).

https://supermotors.net/getfile/933303/thumbnail/exhaustefi.jpg

...the muffler heat shield as it would eventually rust the muffler from the outside.

Mine still haven't. So I don't doubt that a lot of mufflers in your area rust out, but it's not due to the heat shield (which keeps the muffler hotter, and therefore drier).

The 1996 bed has heat shields on the bottom as far back as the rear axle location.

All these trucks that I've seen have body heat shields along nearly the entire Right frame rail. Certainly all '82-96 Broncos are fully-shielded from the firewall-to-floorpan seam (11398), under the passenger seat (114A46), back to the gas tank (112B26):

https://supermotors.net/getfile/1047800/thumbnail/bodysheetmetal.jpg

First, 1987 460s were still carbureted as were the 351 HO engines in the F250/350 over 8500 GVWR. Here are the diagrams from Walker's catalog, they do not show the 168" wheelbase, bit the difference would be in the intermediate pipes (different lengths, used for wheel bases over 133") the 1990 is the parts truck I used, bed on Darth is a 1996 as 1985-86 dually beds are unique to those years and virtually impossible to find in any condition. Unfortunately I do not have any pictures of the bottom side of the bed from when it was being prepped. The 1990 had a heat shield next to the mid-frame tank, that after fighting with trying to make it fit the 1986 frame I just left it off, I did retain the E4OD right side heat shield as even though I do not have a cat, the pipes still run right by that area. There were no other frame rail heat shields on either truck.

1985-7 exhaust system:

[Steve83]

First, 1987 460s were still carbureted...

Yeah, so were 5.8Ls. That's why I said EFIs only. And the heat shields are only on the body - they're along (near) the R frame rail, but not on it. The only frame heat shields I'm aware of are on the Right radius arm bushing, and the '87-89 (gas) fuel reservoir.

[85lebaront2]

First, 1987 460s were still carbureted...

Yeah, so were 5.8Ls. That's why I said EFIs only. And the heat shields are only on the body - they're along (near) the R frame rail, but not on it. The only frame heat shields I'm aware of are on the Right radius arm bushing, and the '87-89 (gas) fuel reservoir.

Yes, Darth has the underfloor, riveted on heat shields, real PITA with the aftermarket seats that were in there when I bought the truck. The original bed did not have any heat shields, but the forward tank had the "ambulance" chassis shield on the tank causing it to rust out where dirt collected. Since the exhaust cross pipe is 35" further away on a crew cab it got ditched when I replaced the tank.

When I re-did the interior, I added extra heat insulation in the front footwells, rear footwell and a section over the underside heat shields. The front seat passenger no longer has the "hot foot" issue the truck always had.

When I did my EFI conversion, the intermediate pipes had been replaced with a welded in section years before, I had the shop use a salvaged flange from a catalytic converter and connect the existing dual pipes to it, allowing a removable front down pipe set (still requires temporarily removing the transmission crossmember to get it off) which will be done when the new engine goes in.

[kramttocs]

As for connecting the two batteries, I didn't explain that there's an optional that I'll install to force the two batteries into parallel. Not sure where I'll install the switch, but I'll also put a warning light on the dash to show they are paralleled.

I've moved into getting all my ducks in a row for the dual battery install. What product are you going with for the switch? I like the simplicity/look of the oem solenoid but the parallel mode to allow jump starting is a nice option.

 

[Gary Lewis]

As for connecting the two batteries, I didn't explain that there's an optional that I'll install to force the two batteries into parallel. Not sure where I'll install the switch, but I'll also put a warning light on the dash to show they are paralleled.

I've moved into getting all my ducks in a row for the dual battery install. What product are you going with for the switch? I like the simplicity/look of the oem solenoid but the parallel mode to allow jump starting is a nice option.

I'm going to use a Cole Hersee 48530 Smart Isolator on Big Blue, but I have its little brother, the 48525, on our boat. The bigger one is rated at 200a and the little one at 85a continuous, which fits the output capability of the two alternators.

The documentation is here, but my favorite features are:

• Automatic Parallel: The two batteries are paralleled when either battery's voltage is above 13.2V for 2 minutes. So you can pull the auxiliary battery down to zero and it won't connect that one in parallel to the starting battery during starting - like the factory relay does.

• Automatic Disconnect: The two batteries are isolated when both battery voltages are below 12.7V for 1 minute. So if your aux battery dies and it starts taking everything the alternator can put out and still the voltage goes south it'll drop it out of the circuit. However, it doesn't work if the main battery goes south.

  I know that for sure.

• Forced Parallel: One little switch can force it to parallel the two batteries, like if the main has gone south and the aux is up.

• LED: There's an output that tells you when the batteries are in parallel. I check that on the boat frequently.

[Steve83]

...parallel mode to allow jump starting is a nice option.

The factory-style relay can do that, with the addition of the switch shown here:

https://supermotors.net/getfile/905422/thumbnail/battrelayaux.jpg

Don't use the relay with the LED - it's not necessary.