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

[Levigarrett76]

I’d like to see a broken crank

Here’s a picture of the 400 crank when I shipped it

Here’s a crank that somehow manage to offset grind itself Guy wanted $50 for this “400” crank. Just another junk 351m

Ill get a picture when i finally pull it and tear it down


And DAMN

 

[WiscoF100]

Someone had poorly welded repair washers of the wrong size for the rear mounts. So I used this holesaw trick to fix that wagon.

With the engine set I could move the cab forward to its resting position. I had kept the cab mounts from my 77 but eventually dumped them somewhere along the cross country moving. Graveyard has cheesy lower cups but nobody repops the upper. I found a thread on FTE probably with good dope on lengths and materials. Can’t remember if it was 3/4” pipe I used? Apparently I didn’t book mark the forum page.

Then I just started laying pieces out. Never put one together, I’ve always hacked them apart over the years.

One example of how meticulous the previous owner was. I appreciate his attention to detail.

I slapped a new core and blower motor in not because they were bad but I’d rather not take this apart again for awhile.

New OE brake booster and the MC is from an expedition maybe? It’s 1-3/8”.

Edit: now I’m second guessing myself. Maybe it’s 1-1/4” or 1-1/8” and Superdutys are 1-3/8”? Think that’s right. Racecar has the SD mc and I grabbed the Exped for the smaller bore but never installed it. Manual 1-3/8 was a lot of pedal to push

Engine getting all dressed out

 

[Provience]

Lots of little work going on, but it sure looks good coming together

 

[WiscoF100]

Tedious for sure.

For the record, the only items that have not been removed, modified or reconditioned are the cab strikers, cab/fender apron brackets and differential carriers.

I’ve resealed the trans pan and freshened up the t-case output seals and gaskets.

This truck was or has been stripped down to every basic component. It’s 100% assembly as it was first born. Been really cool to approach a project from this angle.

 

[WiscoF100]

I wasn’t about to F around with an OEM fuel pickup. This tank is the aftermarket 38 gallon. I wanted ross cawr -6 plumbing and accurately measure fuel down to the last drop with a custom length tube style fuel sender. The dimple for the emission vent would work perfect for the sending unit and it’s centered over the deepest part of the tank

The pickup tube is directed right at the sender and about 1/2” off the bottom

 

[Levigarrett76]

Nice

 

[RunningProblem]

Nice welds.

 

[WiscoF100]

It’s a pain guessing how non-adjustable suspension stuff is gonna sit. This is why the ‘77 went full tube chassis. So I worked tediously slow projecting the ride height, caster and steering geometry. The main issue was positioning the axle wedges so that in the end everything would sit correctly

I had thought about building a fixture for the wedges using the original D44 but it sold before I could do such. I used a trapezoid calculator to figure out width at axle using link length and frame width. Wedges weren’t tacked until I started getting most of the trucks weight assembled. Even then I cut them free a couple times. I squeezed more steering out of the axle and verified link and header clearance. Driver side might run at full stuff/lock. Don’t care.

Duff coil retainers weren’t even close by a mile so I made my own (beefier) 3/16 and bumped the bolt size to 7/16

 

[WiscoF100]

Minnesocold

Laid out the panhard brackets in 3/8. For Christmas I got a portaband setup. It’s pretty handy but has many limitations and eats blades. They’re just over stressed with roller angles and changes. It’s nice because it eliminates black boogers, ergonomical and I can cut at all hours. I avoid any grinding indoors for risk mitigation and air quality etc.

I settled for factory PH frame offset. Wanted more because I like to balance the offset of the link to the rails. It would’ve also allowed more length but couldn’t get carried away with drop and offset because of the radius arm caps. I had plans to offset the steering gear and everything for the longest/flattest links possible. “Stock” builds are incredibly full of limitations.

Length and geometries basically ended up as optimized OE configs and T link steering. There will be a lot more detail posts involving this.

Coil springs will never allow for this but the truck has 7” uptravel. I built with the intention that maybe one day that 10” or 12” coil overs and or 3 link could be grafted without reengineering the steering and panhard.

Another compromise was that I couldn’t move the PH bracket back to give the tie rod room because of the coil spring and radius arm cap. It required offset 7/8 heims to achieve this clearance.

 

[rattle_snake]

The T steering arrangement with those large angles is going to rotate the tie rod. It basically makes a dead spot in the steering, as the tie rod rotates before it moves laterally.

Or, as you hit bumps, the TR rotates freely and allows knuckles to move when steering wheel/drag link is held tight, allow vehicle to wander.

2 fixes:
-make bars flat (like OEM, not lifted)
-connect drag link to knuckle.

Also, it will eat all those rod ends quickly.

My 1st failed attempt. How not to do it.

 

[WiscoF100]

rattle_snake, yes you are correct. This is an issue I corrected with my ultra4 build. It was discovered in a video that filmed the first time leaving the garage under its own power. It’s a lot of wasted effort that dead spot.

I disagree about OE angles. They’re not very flat and people preach flat links but outside of a moon buggy, it’s simple not realistic. I personally don’t mind +/- 10*+ angles as far as handling is concerned.

The fun part of ultra4 4500 class (or the sport in general) is the amount a problem solving and mechanical engineering involved.

This truck will also serve purpose as our pit support truck at the hammers.

It also serves as a parts and concept test bed and a vehicle in which sacrificial harvest can support the race vehicle.

So, the materials, components etc are built with as much interchange as possible. This is why I tried to squeeze 40” drag link and PH but settled for 35.5”

I don’t want to jump too far ahead but there’s drama and conclusion in how I controlled the rotation of tie rod

 

[rattle_snake]

Didn't mean to poo all over your build but share some lessons I learned.

Yes nothing is 'flat' but at low angles the arrangement works fine. It also depends on the goal, trail vs DD on the freeway.


Carry on Sir....

 

[WiscoF100]

No offense taken. You’re sharing what you know, I get that. Sharing a build thread that’s been underway comes with those consequences. I welcome everyone’s input, just because the build is far more progressed than the thread is, I don’t want people to hold back. Your observation is something I would’ve made and I’m glad you studied the photos enough to address that issue

 

[OX1]

Someone had poorly welded repair washers of the wrong size for the rear mounts. So I used this holesaw trick to fix that wagon.

With the engine set I could move the cab forward to its resting position. I had kept the cab mounts from my 77 but eventually dumped them somewhere along the cross country moving. Graveyard has cheesy lower cups but nobody repops the upper. I found a thread on FTE probably with good dope on lengths and materials. Can’t remember if it was 3/4” pipe I used? Apparently I didn’t book mark the forum page.

Then I just started laying pieces out. Never put one together, I’ve always hacked them apart over the years.

One example of how meticulous the previous owner was. I appreciate his attention to detail.

I slapped a new core and blower motor in not because they were bad but I’d rather not take this apart again for awhile.

New OE brake booster and the MC is from an expedition maybe? It’s 1-3/8”.

Edit: now I’m second guessing myself. Maybe it’s 1-1/4” or 1-1/8” and Superdutys are 1-3/8”? Think that’s right. Racecar has the SD mc and I grabbed the Exped for the smaller bore but never installed it. Manual 1-3/8 was a lot of pedal to push

Engine getting all dressed out

I personally always upgrade to the 93ish F350 dual diaphragm booster (if I'm not going hydroboost). I like the dual hole saw trick, very cool.

 

[WiscoF100]

93ish F350 dual diaphragm booster

Hmmm something I did not know about. I’ll have to look it up sometime. 👍

No coffee yet but there’s some items on this truck that aren’t permanent fixtures and I left room for comparison or upgrades down the road on purpose. Example: I’m rocking the rear drum brakes. I saved the disc swap for labor timeline and to see what kind of difference they make.

 

[Levigarrett76]

Hmmm something I did not know about. I’ll have to look it up sometime. 👍

No coffee yet but there’s some items on this truck that aren’t permanent fixtures and I left room for comparison or upgrades down the road on purpose. Example: I’m rocking the rear drum brakes. I saved the disc swap for labor timeline and to see what kind of difference they make.

Anxious to hear your impression on the drum/disc rears. I have an unpopular opinion in that regard.

 

[WiscoF100]

Levigarrett76 what opinion is that?

The koh racer has Dayton dual pistons on the D60 and the all too typical Chevy calipers on the rear. Couldn’t tell ya what my pedal ratio is/was. The MC was the 1-3/8” Superduty, manual, no booster. The truck stopped but I wouldn’t call the brakes great.

This truck is more or less the same setup but vacuum boosted with the smaller bore MC.

The race truck is going to receive dual piston rears. I’ll be using the pin style brackets from the whoop scissor F250s. The daytons have 1.18” more surface area than the Chevy caliper. Additionally I’ll reduce the MC bore and have a crazy pedal ratio. It’s Erik Miller that I credit for wanting matching calipers. He figured that out a couple years ago. Even the top names don’t know everything. He shared his tech that mismatched caliper sizes were disturbing the cars in the rocks and breaking stuff.

 

[holdmypocket]

One thing I personally ran into on my 78 was the frame where the steering box bolts up to was cracked to shit. It looks like you've probably had a few of these trucks, have you run into that issue?

I welded a 3/8" plate to mine (with a radius at the front and all the corners) when I was still daily driving it and it held up fine but it wasn't the best design (didn't wrap underneath the frame rail) and now that I'm going to 40's I'm thinking about redoing it so I'm curious to see how other approach this.

Love both rigs by the way, getting me excited to get back to work on mine.

 

[WiscoF100]

Haven’t had a cracked frame yet. Don’t recall if I saw the frame repair in your thread. I’d think what you did is sufficient but maybe gussets from the back side to help tie it altogether with the cross member would be the end all.

I’ve unofficially had 9 of these old trucks. Last one became a tube chassis and this one will be a daily with 37s and the usual suspects for parts found on trail rigs. I’ll probably eat lots of humble pie

This truck is fully prepped for axle mounted hydro assist and I want to fab a supplemental brace behind the panhard that triangulates to the front cross member. When I say prepped, I want to drive this thing a minute with no assist and the slow 18:1 ratio. I’m building a highly ported 15:1 box.

That build is delayed because I got in a rush. I need to have this part crack checked. Noticed 2 cracks right as the first coat of paint hit. Probably dumb, but I hope it’s not cracked all the way through?

 

[rattle_snake]

On the rear drums, for me they work well enough. In addition to a prop valve at max, I had to go down 5-6 sizes of wheel cylinders to keep them from locking up at max brake effort. I like the idea of discs for weight loss, but not sure they would have much performance benefit. And loosing parking brake or paying for it.

Interested to hear before/after from someone who has done it.

The down side to drums is the servo effect, controllability. And the fucking springs and shit.

 

[Levigarrett76]

On the rear drums, for me they work well enough. In addition to a prop valve at max, I had to go down 5-6 sizes of wheel cylinders to keep them from locking up at max brake effort. I like the idea of discs for weight loss, but not sure they would have much performance benefit. And loosing parking brake or paying for it.

Interested to hear before/after from someone who has done it.

The down side to drums is the servo effect, controllability. And the fucking springs and shit.

I share your opinion. Back when i street drove a truck with 44's, stock 10.25 drums stopped them better than the typical chevy caliper disc conversion.

 

[WiscoF100]

Maintenance and weight savings are obvious pros. If these drums didn’t have new shoes, springs and wheel cylinders I would’ve immediately tossed them in the garbage.

The chev calipers haven’t impressed me but I’ll give them a try on this rig.

 

[rattle_snake]

Well if you don't like 'em, send them to me. I seem to keep adding weight and not much left to go the other way.

 

[OX1]

Hmmm something I did not know about. I’ll have to look it up sometime. 👍

No coffee yet but there’s some items on this truck that aren’t permanent fixtures and I left room for comparison or upgrades down the road on purpose. Example: I’m rocking the rear drum brakes. I saved the disc swap for labor timeline and to see what kind of difference they make.

Easy install starting with a couple of square tube brackets and grind booster rod a bit.
Use a 86 Mustang SVO MC, which uses the exact fittings that 78/79, 1/2 tons have stock and is 1-1/8 bore
(not hydroboost big, but decent size).

It's about the same dia as stock booster (70's half ton) and dual diahpram. WAY better than "normal" upgrade of 79ish f350 smaller dual diaphram (which I tried and thought sucked).

Don't want to spam up your build thread anymore than what's here. I did a spliced up/hacked set of "setup" brackets, using the stock mounts. Most of the pertinent dimensions are in this folder.

Index of /GREEN_DILYSI/93 F350 BOOSTER

 

[WiscoF100]

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.

 

[WiscoF100]

There’s a saying that goes something like nothing is permanent unless it works or permanent isn’t temporary unless it works.

The character of this truck is to show its a work in progress. To dial in the front suspension I had to load the truck up to operating weight which just meant temporarily assembling parts permanently.

I had to find a bed. Used prices are dumb. I could buy a whole truck out west for what idiots want for OEM beds and it’s hard to find short boxes. Build details to come but this is from that new company in Georgia. They were pretty easy to deal with and I got my parts fast.

The front geometry started to materialize once I got the tie rod and knuckles in double shear. 1/2” plate tie-ins

Future me wants to kick history me’s ass for not spacing the passenger side for a drag link heim. Spoiler alert. That’s ok I’ve got a lathe now and the misalignments only need a hair off the top

Redneck alignment. I square off the long side knuckle to “center” all the steering geometry

Nordern lites

If anyone is interested, I have a lot of cycling pictures or clearance of the components. It’s capable of 7” uptravel and the only interference is the tie rod and panhard bolt

 

[WiscoF100]

Continuing to bring parts out of storage and add them to the truck. Doors were next after I installed the bench seat. He hadn’t yet touched the passenger side but began the driver. I had to bandaid a couple items so it was safe to hang on the truck. It was also the first time I could inspect the bottom side. Discovered they’re pretty much gone from the inside.

Some detail how I swept a center punch across the tube to find center.

There’s a machine shop on eBay that is piece these weld bungs from. I use them for anything but rod ends.

Fancy yacht

One thing I dislike about forward swing boxes is how far forward the drag link has to sit. If it weren’t for wanting quick ratio I probably would’ve converted to rear swing. If this was a linked rig, I could’ve done some fancy work to move the box rearward and panhard outward

More or less the final (for now) version of the steering. Tie rod control and hydro updates yet to come. I’ll post the angles once I begin final assembly. But for now, everything is equal length and angle. I had to settle for a slight 1.5” vertical separation in the links.

 

[WiscoF100]

The pitman arm was slugged with 1” DOM at probably 10*. I’m sure the links are 10* too. Drilling it wasn’t rocket science. I just jumped in with both feet. I used a step drill to hog away most of the material and pilot the 1” bit later. Worked slick.

For radiator I chose a 3 row champion with dual fan option. I was a little disappointed that only their custom order rads are made in USA not the OE replacements. It seems of nice quality anyways

Don’t want to waste everyone’s time with silly hydro assist mock up pics. Goal was out of harms way, decent geometry/packaging and utilize the full stroke without limiters. PSC 1.75” x 8” x .75”

I prefer to keep them on the frame side rather than the axle (like I build sooooo many off-road trucks 🤣) but wanted try this approach which is the majority of how many are installed. One requirement I wanted was to offset the piston/rod oil volumes opposite of the steering gear. Meaning hydro piston extended stroke steering gear retracted stroke. This should help balance the forces and mitigate the return oil restriction. Make sense? I don’t want to share much more of my steering brainstorms until I prove my concept and successfully compete at king of the hammers again. It’s not ground breaking tech but I need to know it’s not a failure and works before I put it out there

Here is one concept of tie rod control. I pissed off everyone on FB because of this. It’s a split between a revelation I had many years ago and that of an active 4500 racer. It works-sort of. Worked perfectly until I discovered my tac welds were stretching, ok so I nailed down a couple more. Now it had some issue, it cycled effortlessly but had one hard spot, guaranteed to eat something up. There’s quite a few examples of rigs with similar setups but I dumped the concept.

This is what the race car has but I didn’t have room to package it and I believe it only works if the rod end is above or below the tie rod. First example I knew of was spidrs 8 ball and recently rants 4600 bronco. I’ll share the final concept in another post.

Now stop chasing me with pitch forks and torches and enjoy this truck I never should have sold….or do chase me with torches because of that

 

[WiscoF100]

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.

And autocorrect is having a bad day. Sorry for some of the dumb text in previous posts. I don’t catch all of it as I’m trying to make these updates quickly as possible.

 

[Levigarrett76]

The hell with typos, we just appreciate the content.