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1978 F-fun hundred 3/4 tons and 37s

I feel like I’ll be re-reading this post quite a bit to digest/understand it! Do you have a build thread or more info on the ultra4 truck?
 
Real time question for the dentside aficionados…

My gauge cluster is very much mechanical sweep not idiot lights (18 pin in theory)

The trucks wiring harness is very clearly 14 pins (idiot lights)

The long story is that I do not want a factory cluster and am only considering it for the speedometer for the upcoming test drive. Will it cause any electrical gremlins if I do or do not plug it in? Immediately I think about headlights or turn signal function…..
 

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I feel like I’ll be re-reading this post quite a bit to digest/understand it! Do you have a build thread or more info on the ultra4 truck?
I hope my info is clear. Not to sound like a know-it-all but I’m a wealth of knowledge (and dumb ideas) and love to share and absorb information but I’m not much of a composer in text. I’m stubborn but I’m not an asshole although I’ve probably made a bad name for myself via the internet due to fatigue and half baked thoughts just to make an untimely post.

There is a build thread on the old board but nothing current. I keep the ultra4 close to my chest until I race again. Myself and the build have matured greatly….still many improvements to be made. I don’t know whether I want to make a thread and stop before the good stuff or just wait until after I race to share it again.

Not sure if it will ever race again because of the roll cage drama…..at that point I’ll just have a complicated trail rig. The new chassis is 1.75” and while 2” would’ve been smarter I had my justifications and it’s legal until the rule changes. If only the god damn Karen’s who do not race would shut their mouth and quit adding their 2 cents to a sport they don’t have ownership in.
 
Thanks for the tech OX1 !!

I’ll try the 1-1/8” MC if this 1-1/4” doesn’t work out. Do you run or proportioning valve? Does anyone have a preference?

I’ve always dumped them and run direct off the MC.

I run the stock proportioning/distribution valve, gutted for the rear circuit, for disks. Main reason I keep them is I don't need to redo tubing.
You can unscrew the actual prop part, gut the valve part of it, then screw it back in. It will then just be pass through to rear. Does allow you to
keep warning light, but not sure who might have ever needed one. Any time I lost even only one circuit, felt like I had ZERO brakes.

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Real time question for the dentside aficionados…

My gauge cluster is very much mechanical sweep not idiot lights (18 pin in theory)

The trucks wiring harness is very clearly 14 pins (idiot lights)

The long story is that I do not want a factory cluster and am only considering it for the speedometer for the upcoming test drive. Will it cause any electrical gremlins if I do or do not plug it in? Immediately I think about headlights or turn signal function…..

Head/running lights are fine. Not sure if signals might be a hair slower, if cluster indicator is not in the circuit.
 
OX1 by that mod to the valve, is there any function left? Honestly I’ve never analyzed one before, I’ll study that picture some more and absorb it.

Instruments….forgot to mention, I have no idea if the cluster is OE. Previous owner could’ve swapped it. He was hoarding parts to create the truck how he envisioned it.

The seat belt light and both turn indicators work.

No gauge lights or high beam indicator.
Cluster installed simply as place holder…hoping for functional fuel gauge. Speedo won’t be accurate but again it’s a place holder in the transfer case.

No blower motor

No windshield wipers

Have not verified fuses yet
 
OX1 by that mod to the valve, is there any function left? Honestly I’ve never analyzed one before, I’ll study that picture some more and absorb it.

Under normal operation, the spring loaded spool for front, delays the fluid pressure (since drums typically take more time/pedal travel to actuate) to the front calipers and the rear "proportioning", reduces pressure to the rear drum brakes, to prevent drum lockup upon severe brake operation.
I don't know their full operational curves/pressures, etc. On my 78/79 broncos, I only gutted the rear section (which again makes it just pass through) . On both my fox bodies (84/86), both also have rear prop setup gutted, but they both use an adjustable in-line prop valve for rear disks.

I've never tried removing front delay valve (or removing entire stock prop valve). It's possible with 4W disk, that that valve is now hurting "performance" I guess. But except for my offroad rig, my 79 street and both fox bodies are now hydroboost, which "hides" any other deficiency you typically may have in your brake system, pretty well. Might be why some claim better performance, by ditching late 70's propr valve, altogether.

For kicks, I dug up my fox body shop manuals.It does not show or discuss any "metering" valve for the front brakes.
Maybe it was then incorporated in MC, but it does not discuss it at all, and manuals back then discussed operational
theory pretty well.

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Also, this thread shows an 86 F150 prop valve, which also appears to have eliminated metering section (of mid/late 70's).

Trouble with 1986 F150 Xl 5.0v8 proportioning valve - Ford Truck Enthusiasts Forums

I prefer hydroboost really, but on my offroad rigs with steering ram, I don't like that fluid pressure/volume has to go through HB brakes, before it gets to steering (typically how HB is usually routed, hydraulically). I did the numbers on "boost" (max added force) between that 93 F350 booster, and an older style hydroboost (like 70's Lincoln's, which is what I have on my street 79 with 35 AT's and tows a 5000 lb+ boat), and it was pretty comparable, using say 18 in HG engine vac compared to 1200ish PSI PS pump pressures.
 
The front disc delay gadget doesn't really do much. I rebuilt one, started leaking so removed, no change.

The rear 'proportioning' valve function typically was for reducing the rear pressure spike when slamming on the brakes, to prevent rear lockup. Rear lockup has a lot to do with weight in truck, tires, road conditions. Likely won't notice if it is there or not.
 
Thanks for the explanations. I got a better idea now of its purpose. Will soon test the theory as I’ve never had a disc/drum without it
 
Can’t edit my post above.

Need to clarify some info. Hydro cyl extended is full oil volume. Steering gear extended is reduced oil volume due to the ball/worm race. And vice versa. That’s how it’s configured.

Mine is installed the same way, drives just fine down the trail or highway
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If theres a difference in speed from left to right i cant feel it at idle, or at cruising RPM.
 
Mine is installed the same way

Sort of, but your box is inboard which pairs up the high/high low/low oil volume

Here’s a diagram to back my explanation
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The following is developed using crude calcs
#’s derived from “off center” values

(1) Ford steering gear: 3.12 bore, .75 shaft and 1” travel
(2) Assist cyl:
1.75 bore .75 shaft 4” travel

Force
(1) 11,468 push (2) 3,608 push = 15,076
(1) 10,805 pull (2) 2,945 pull = 13,760
Opposing push/pull
The forces are equalized = 14,413

Volume
Extend (push)
(1) 125.28 ml (2) 157.66 ml = 282.94 ml
Retract (pull)
(1) 118.01 ml (2) 128.704 ml = 246.72 ml
Opposing extend/retract
253.99 and 275.67

The closer you balance the numbers the greater you optimize the system

I don’t want to share more than that right now…hence why this truck is a streetable test bed for ideas/mods I’ve come up with to verify if they work

The ultra4 was same/same and under most circumstances there was no noticeable difference. Under high stress, right turns were noticeably less powerful, slower and borderline hydro lock when quickly chasing the right after a left turn. Most of it was solved with 1,600 psi 4.5gpm TC pump. (Prior to ever racing king of the hammers) KOH was without issue steering wise. Never broke the system, never ran hot and powered through most trails but really it was just another cookie cutter hydro assist setup. I want more
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reptillikus is your assist 1.5” ? And I’m not grumpin on your setup, I had just never dumped all my squirrels nuts into text before

Checked the panhard angle
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BTW I went full 7/8” heims on the steering links. KOH rig will follow suit. The panhard bolts are 7/8”, steering is 7/8” with 3/4” misalignments. The threaded inserts are from Trailforged. It’s not my story to tell but the company had something to do with a past and present forum member. They’re beefy, well priced and best of all even if you booger weld, you can still fit a damn wrench on the flat. I fully believe in these and keep stock of them. Far left I buy from eBay. I use them for fasteners but not heims. 3rd was from midnight 4x4 and used as a sector shaft support bearing pivot/pitman nut, 2 Trailforged in 7/8 & 1.25” and 6th is M4x4 1.25”. I hate RuffStuff thin wall and barely any pilot shoulder fittings. They live in my junk bin
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Here was my first attempt making the panhard frame bolt. 7/8 LH cut by hand. It wasn’t concentric. Variety of reasons it cut funny, me doing it by hand and hardware store bolts can be real funny in the larger sizes. But why did I want a fine left hand thread? Because of space limitations on the back side hence integrated weld-in threads and I can leverage a wrench a lot easier in the wheel well than under the truck working towards a lot more stuff in the way
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Second attempt. Right tool for the job
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Those are nice weld-in fittings, i like those better than the stuff i used.



Where's the hatch marks so you knows its a LH bolt? :flipoff2: J/k, nice work :smokin:

reptillikus is your assist 1.5” ? And I’m not grumpin on your setup, I had just never dumped all my squirrels nuts into text before
Yeah i get it. I first added hydro assist in 06 and didnt have any clue what i was doing, i just knew i needed it :laughing:
It was later on that i realized some of that stuff is important.

These days im at 2.1º. Thats not because 2º somehow seemed better, its a packaging issue with my setup
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My fixed mount is set as high as it can go w/o interfering with the lower tracbar bolt
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and on the tierod i made a clamp mount so i could adjust the toe-in easier. This thing is a street cruiser in addition to trail rig so getting the toe spot on seemed important.
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This caused its own issues, because if i rotate it down to decrease ram angle, it will contact the diff cover
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I know single shear isnt ideal, which is why its a 1/2" tab. Fortunately for my application (weekend warrior/trail rig), it doesnt seem to matter.
 
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Where's the hatch marks so you knows its a LH bolt? :flipoff2: J/k, nice work :smokin:
Good eye, sir!!! It crossed my mind once for style points but I kept spacing it. The bolt is incomplete in other regards too. I was boring and tapping the ends of all the bolts for safety caps but by the time I got to this one I had burned up all my drills and broken 1 tap. It’s probably permanent at this point because I want to drive this damn thing. Getting impatient.

Your cylinder mount is nearly identical to what I came up with! I settled upon using a clamp on the tie rod as well for alignment. The geo was better with tabs but I didn’t want to be locked in one position since I’m using 1” offset heims at the knuckles. 🙄

Do you have any issues of the clamp slipping?
 
Yeah my first setup was 2 tabs on the tierod. Then I bent it on a rock and realized how dumb that was :laughing:

I haven't had any problems with the clamp mount. I thought for sure it would move when bound up in the rocks, but thus far I haven't had it move once.
 
Not sure what I was capturing here but it shows the offset heim joint real well.
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First rendition of the wobble stopper or idler link. While this truck isn’t a hardcore wheeler, I didn’t want anything below axle C/L. I prefer to build with the rock racing mindset
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Mounting the hydro cyl with a clamp so as not to back myself into a corner with alignment issues. Going to cut this stud off and weld tabs to the clamp
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As I got the truck closer to curb weight I could tell the rear was low. Don’t remember how I magically guessed but I chose 1.5” as a riser. Cut these plates out from scrap and used 1” strap from the hardware store for the perimeter. I got the capture holes idea from some lift blocks sold on eBay
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I certainly like how spacious the underside of this truck is, without a lift I’d be really miserable working underneath it
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Mostly completed circuits and ignition box mounted. I Canniblized the origin of the harness where the alternator, solenoid and battery would’ve been. My focus was utilizing heavy gauge fine strand wire leftover from the race car for the self exciting 3G alternator, CVR high torque starter and the cab wiring. Everything is mega fuse or circuit breaker protected.

The battery is directly ground to the body and engine block. The block serves as a junction to the frame and alternator. The engine is grounded to the cab. Redundancy.
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So far the electrical system is functioning as I perform my final system checks. The blower doesn’t work, no instrument lights, no wipers and I don’t know if the starter works. Waiting to prime oil/install torque converter bolts before I bump it over.
 
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Pictures of brazing the pitman bushing and hydro assist fitting with silicon bronze.
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I wasn’t happy with the OE pin top shocks that came with the kit. They were on the short side. Not sure why how but I came up with the idea to convert the rear frame brackets to 1980+ style. They fit the bill for wanting 10+ shock travel. The originals were on the crusty side anyways. Kept a fresh edge on my air chisel and made quick work of the rivets.
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Next came the front brackets. This was totally someone else’s idea but not sure where I found it. A lot of EB, Jeep and Toyota type builds source these. They are 80 somethin F-250 application. Again much taller and normal 1.5” bushing spacing. I used the lower hole. The upper was marked for the correct dentside spacing. These brackets kick a little sooner so to keep contact with the frame , they’re slugged with 3/4” DOM. Squint closely and you can see in the last pic. I don’t remember offhand how long the shocks turned out.
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As a way to surely sleep on the couch on my anniversary I asked my wife to help me with the hood after our date. Still married.

I used a cheap led shop light for under hood and interior work lighting during this project. As mentioned this truck is a custom with round lights. I went back and forth trying to figure out what I wanted and chose rectangle. I had all the stuff as the previous owner had collected them for his vision.
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As I went through different spurts of motivation, I unpacked all the bed sheet metal before the never ending winter arrived so that I could for real install and plumb the fuel tank and other under chassis stuff. In order for my sending unit and the gas tank in general to fit under the bed floor, it had to be mounted lower than what the kit supplied for bushings and bolts. The frame needed a notch so that the filler neck would have a smooth transition.
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Chopped off the shackles and replaced with 9/16 hardware for easy future upgrade of my long travel shackles
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I had recently purchased a hydraulic press when there was finally inventory and a coupon that aligned.
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Made a quick and dirty brake from scrap. The receiver die is actually the gas tank bushings sleeved with the 5/8 bolts from my leaf springs
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Looks good but I discovered another close clearance and lowered the tank a hair more
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In trade school I had a teacher who loved to say “don’t be a sissy, cut it up” as he was holding a sawzall
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The hose kit is from bronco graveyard. I reshaped the stainless pinch chaff guard whatever over some 1-3/4 for a wider profile and less choke point. Thought I was being clever and built a FATS style vent. It was kinda cool but really started getting on my nerves seeing this useless eyesore hanging below the tank from the rear
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I dig the fix for the pinched filler hose, that shit has always made me wonder.:usa:
 
Help me understand the long vent. I get the FATS aspect. How is that better than vent into filler? Are you putting a check valve in the fill tube? What is issue to solve?
 
rattle_snake the answer to your question begins with I did not have a filler neck. They’re not reproduced. I’ve been on a wait list at wild horses for a year (just for fun)

The fill neck doesn’t come until later chronologically but since you asked, here’s the details.

Referencing a truck of someone who I bought parts from on marketplace I went about fabricating my own fill neck.
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I wanted a reliable modern cap so I sourced a J1114 threaded cap and 2.25” diesel or non-baffled neck. The elbow is a 60* stainless exhaust piece.
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Couldn’t find any threaded neck’s available in stainless. The two pieces are fused with silicon bronze. Could’ve used SS filler or even mild but I did it this way. I got a bead roller die set really cheap with a stacked coupon on top of a Xmas sale at Eastwood. All in including tools I’m still cheaper than a new chinesium part that’s backordered.
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Why no fill vent? I assumed I’d never find a tight radius 3/4” elbow right off the bat in addition to being unsure of cap ventilation. That’s why I first built the fats vent. All around solution. But I got tired of staring at the stupid vent hose. I searched and bingo found an elbow for cheap. Then I dissected the fuel cap to find my answer. It appears at first glance to be pressure relieving and vacuum relieving. However, upon dumping 5 gallons in the other day, I quickly discovered how wrong I was. About an hour later I thought I saw something from the corner of my eye as I was filling the brake master. I shrugged it off. Once we started bleeding the brakes that’s when I saw it again and noticed my fuel rail leaking. I had just previously turned the engine over for the first time and was impressed my pump primed that fast. Then I had another suspicion, I unlocked the cap and whooooooosh came the vapor. I modded the cap to ensure that the 2-way check vents positive pressure now.
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Maybe today but more likely tomorrow as I’ve been awake for 24hrs and need to sleep away my weekend, I intend to take it on its maiden voyage and test the fill neck at the gas station. Spoiler alert, my break-in run was not glamorous and probably the most disappointing first start I’ve ever had. The only good news is that chooched first try of the key. My hopes aren’t high otherwise.

There you have it rattle_snake lol
 
With the tank install, wiring and plumbing complete I moved on to constructing the bed. It was very well packaged. I’m very pleased. The crate for the bed floor has gifted me with lumber and osb that I have used time and time again on major house renovation projects.
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Very thankful to have a 28’ deep garage. Most around here are single stall shacks
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You’ll need/want a variety of locking clamps and 2” C clamps. I built this thing 100% solo no help. I had all 4 pieces clamped together within 6hrs roughly. Then 131 spot welds were drilled
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Ford Era has a decent video documenting a bed build in 1 day but his, mine and ymmv. There are some self alignment features built in but there are a couple errors that you have to override and just get it set to your liking. The front panel flange ended up being offset seen below. Equalizing the flange gap throws the bedsides out on top.
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The bedsides have a tang and the front panel has a square hole that are suppose to catch on each other. Again one side worked the other I had to wing it to get the alignment that I determined was right for me.
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Before welding I used a bunch of stainless self tappers to see how it looked on the truck. I didn’t need to but couldn’t adjust the bedside much anyways. I had a small concern about the passenger side meeting the cab/dentside. To my eye it wasn’t perfect but you can only see one side of the truck at a time. My focus was setting the driver side in its optimal alignment since I’ll see it more.
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OEM tailgate fits perfectly. I was able to manipulate the alignment pretty well back here. You can a ratchet strap along the bottom. I used a 2x6 from my crate to adjust to top gaps along with a strap. The tailgate was fully refurbished inside and is even the correct color for the truck. I scored OEM bed strikers and scissor links for cheap on eBay. All the hardware holes and captive threads have a good range of adjustment on these bedsides. I did rework one of the driver striker to get optimized fit. It’s all finished off with the correct bumpers etc and closes like new.
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Tips for purchasing this bed. Call them (AMD) don’t rely on the website. They were very helpful and my lead time was very short.

If you didn’t have an OEM bed to compare against, you’d swear this was the real thing. There are a couple glitches in the matrix but aren’t critical in my opinion. You will notice tooling marks but they are concealed. The actual body panel is smooth and straight. For most guys sand and paint.

The biggest issue I came across and has been consistent with FB groups is the taillights won’t fit. Driver side I think I only had to massage the steel with hammer and dolly. Passenger side I had to sand the taillight to fit and hammer dolly. It won’t fit by a mile otherwise. I have not addressed this with the company but intend to as it will be helpful for all
 
AN vise blocks. Must have. It makes building hoses enjoyable and I can say leak free.

None of the plumbing leaks but instantly had a header gasket shit the bed, rear pinion leaks (most likely bad yoke/overfill). Somehow missed a missing transfer case mounting bolt on the adapter. It spewed plenty of oil to alert me on short test drive. I feel real stupid for not realizing it was missing. Plenty more to share but I’ll get there
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Thanks for posting about the bed, I plan on going that route instead of working my current one when the time comes. This thing is coming together fast and looking good. :beer:
 
Thanks for posting about the bed, I plan on going that route instead of working my current one when the time comes. This thing is coming together fast and looking good. :beer:
Thanks! It’s turning out how I imagined it so far. The bed was hitting the easy button for sure.
need me an AN vice block that that....
So much easier than wrastlin a couple a box wrenchs
 
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