Hoss Bronco Build - 1972 Modern Wheeler

[hossbronco]

This is the build thread for my 1972 Bronco Sport Explorer. The goal is to make this into a modernized offroading machine. In summary, here are the build specs:

7.3L Godzilla (645 lb-ft @ 3,900 RPM, 630 HP @ 5,900 RPM), 6R80, Atlas Pro 3.0, 609 Front Axle (Kingpin, 40 Spline Big Bell RCVs, HP10, ARB, 5.14 Gears), 14 Bolt Rear Axle (40 Spline, ARB, 5.13 Gears), 40 Inch MT Baja Boss M/T

I apologize in advance as progress is going to be slow on this, and I’ll probably worry about the body last, at least where I can.

Here’s what I’m planning. I’ve marked the things I already have with a dash. The rest is either on order or still being considered. Also, please note that I’ve decided to put 37 inch tires on and beef up the rear axle some so I can wheel it while I build out the suspension and full-width axles.

Engine:
-7.3L Godzilla
OBR Controller (Controls Oil Pressure)
-Ford Performance Low Profile Intake Manifold
-Ford Performance GT500 92 mm Throttle Body
-BTR Camshaft with VCT Limiter at 8 Degrees
-Johnson Reduced Travel Lifters with Link Bars & Axle Oiling (2126LSR)
-Manton 504 Pushrods
-PAC 1282LX Springs and R393 Chrome Moly Retainers
-ARP2000 Head Studs
-Swiftek Billet Valve Covers & Coil Covers
-Indy Billet Fuel Rails
-Mast Motorsports -08 AN Braided Fuel Cross Over
53 LB/HR Injectors
-ARP2000 Main Studs
-Holley Timing Chain Cover
-Holley Front Accessory Drive
-Innovators West Crankshaft Damper
-Dailey Dry Sump Oil Pan (Billet 6061 T6 Aluminum) and 5 Stage Pump
Upgraded Ignition Wires
Outerwears Pre-Filters
-DC Power Billet 270 Amp Alternator
Dual Odyssey Extreme Batteries (ODX-AGM34/78)
Genesis GEN3 Battery Management System

Transmission:
-Gen 2 6R80 Transmission
-GPZ Frictions and PBH Steels
-Modified Center Support
-Billet 300M Intermediate Shaft
-Billet 300M Forward Shaft
-Billet Forward Planetary
-Gen 3 Billet One Way Low Reverse Clutch
-Upgraded Pump Bearings
-Superior STL009 Sure-Cool Cooler Flow Control Valve
B&M 7 Qt. Transmission Pan
-Lokar Shifter (Future: Modified for Quick Reverse)
-Gen2 Quick 6 Controller with Remote OLED Display
-Circle D 258MM Pro Series Torque Converter, 2200-2400 Stall, Mechanical Diode, Heavy Duty Upgrade

Transfer Case:
-Atlas Pro 3.0 Transfer Case (Clocked Horizontal)
-Long Input Shaft
-Short Tailhousing with 300M Output Shaft
-1300 Series Flange Front and Rear
-JB Custom Fabrication Twin Stick Cable Shifter
JE Reel 1410 CV Canyon Crawler Driveshafts

Current Front Axle:
-Dana 44
-Disc Brakes
4.88 Gears
Chromoly Shafts
-Warn Premium Manual Hubs

Future Front Axle (Stretched):
Spidertrax 609 4” 4130 Chromoly (69.25” Wide)
Gearworks HP10 3rd Member (3.812” Case)
5.14 US Gear Shot Peened, REM Polished 10” 9310 Ring and Pinion
ARB RD249CE Competition Air Locker
Tubeworks Duplx Pinion Support
Billet 1480 Drive Shaft Yoke
WFO High Pinion Diff Guard
40 Spline Gun Drilled 300M Big Bell RCV Shafts
ECGS KP540 Outers with 40 Spline Manual Hubs
8 on 6-1/2” Bolt Pattern
Artec Ram Mount
Artec Upper Truss

Current Rear Axle:
-WH Super 9 Housing (large bearing billet ends, 3"x0.250" tubes)
-Weld-On 3/16" Center Section Skid Plate
-35 Spline 4130 Axles
-Timken SET20 Tapered Roller Bearings
-WH Wrap Trap
-Strange Pro-Offroad Nodular Iron 3rd Member (3.250" Case), Solid Spacer
-35 Spline Competition ARB (RD99CE) Locker
-4.86 Gears
-Strange Billet Aluminum Daytona Pinion Support
-Strange Chromoly 1350 Yoke
-Stretched 1.25"

Future Rear Axle (Stretched):
14 Bolt
5.13 Gears
Billet 1480 Yoke
40 Spline Gun Drilled 300M Shafts
ECGS 40 Spline Outers
8 on 6-1/2” Bolt Pattern

Steering:
-Radial Dynamics Pro Series TC Power Steering Pump (4.5 gpm, limited to 1,450 psi max pressure)
-Radial Dynamics 6061 Aluminum 3.5” Gen II Vortex Remote Reservoir with 5 psi Reservoir Breather
-Radial Dynamics Remote Power Steering Filter Assembly
-Radial Dynamics 3” Billet 6061 Inline Finned Tube Power Steering Fluid Cooler
-PSC Hydraulic Assist with Offroad Designs Tie Rod Clamp
-4x4x2 Power Steering Box
James Duff Tie Rod Over Bumpsteer Eliminator Steering System
Busted Knuckle 7075-T6 Aluminum Drag Link and 1-3/4” Tie Rod (or Rock Krawler) (Future)
Busted Knuckle High Steer Arms (Future)
-Ididit Tilt Column Black Powder Coated
-WH Custom Lower Steering Shaft
-WH Mark 9 GT Black Steering Wheel with Leather Wrap

Brakes:
-Wild Horses MOAB Hydroboost System
-Wilwood Master Cylinder
Wilwood Dual Pedal Cutting Brake
Wilwood 6 Piston Disc Front and Rear (Future)
Wilwood Electric Parking Brake (Future)
-Disc Front and Rear (Current)

Fluids / Cooling:
-Ron Davis Double Pass Aluminum Radiator
-SPAL 19” Brushless Fan (IP68, 850W, 4,000 CFM)
-Lingenfelter Fan Controller
-Derale 15870 Fanned Transmission Cooler (800 CFM)
-Custom Peterson 2.3 Gal. Dry Sump Tank
-Peterson Vacuum Regulator
-Peterson Pop-Off Valve
Setrab 50-948-7612 ProLine Oil Cooler with Brushless SPAL Fan
-Improved Racing Remote Oil Filter Mount with 205F Thermostat
AMSOIL EAO52 (or EAO26) Oil Filter
-Peterson 08-0420 Oil Breather Can
PSC RV00 Vented Catch Cans with Rollover Valves (ARA1?)
-M1A1 Stainless Steel Fuel Tank
-Aeromotive Phantom Stealth 340 LPH Fuel Pump
-Aeromotive 10 Micron Fuel Filter (12350)
-VaporWorx Returnless PWM Fuel System
Discriminator Valve (Gasoline Evap System)
-8” Vapor Trapper

Exhaust:
Modified Twisted Steel Headers, 304 SS, Ceramic Coated (3/8” Flange, 1-7/8” Primaries, 3” Collectors)
Borla ProXS 304 Stainless Steel Mufflers
3” 304 SS Exhaust
Exhaust Cutouts, Vacuum-Actuated (QTP?)

Suspension:
4-Link Front with Trac Bar and 16” King Coilovers 2.5 with SDi E-CLIK Remote Reservoirs
Double Triangulated 4-Link Rear with 16” King Coilovers 2.5 with SDi E-CLIK Remote Reservoirs
Busted Knuckle 7075-T6 Aluminum Link Bars
-2” Body Lift
Spidertrax Sway Bars (7075-T6 Arms, 300M Shafts)

Tires and Wheels:
37x12.50-17LT Mickey Thompson Baja Boss M/T (Future: 40x13.50-17LT)
17”x9” Baja Built Outlaw Forged Aluminum Beadlock Wheels, 8 on 6.5”

Exterior:
Jeep Steel Blue Metallic Paint
Custom Full Roll Cage (Behind Dash)
Custom Prerunner Bumpers
Custom Sliders (Trimmed Rocker Panels)
Aluminum Skid Plates with UHMW
-Heavy Duty Wipers
-HID Projectors Halo Black Series Switchback Headlights
-Alice Turn Signal Mod
Warn Suckdown Winch
Rear Warn Winch
-Rear Quarter Panel Guards
-Upper Quarter Panel Guards
-SS Quick Remove Door Hinges
-Door Checks
Optional Tube Doors
Hyperformance Tough Windshield
-Black Diamond Rampage Soft Top
Mike’s Metal Worx Wing Vent Window Delete
Extended Wheel Wells
Baja Designs Lights
Tailgate Assist
CJ7 Side Mirrors
-James Duff Hood Struts
Billet Aluminum Headlight Bezels
Disruptive Restomod Billet Tailgate Handle

Interior:
-Black Leather Corbeau Baja XRS Suspension Seats with Heaters and Lumbar Support
-Black Leather Corbeau 40” Baja Bench with Head Rests & Heater (Future: Perforated Full Grain Brown Leather with Seat Coolers)
Retractable Seat Belts (Future: Optional 5-Point Harnesses Front & 4-Point Harnesses Rear)
-BC Broncos Console
Fuel Pump Access Panel
-Rosen Aircraft Sun Visors (Future: Dual Visors)
-DB Metalworx 3003 H14 Aluminum Door Panels, Anodized Black

Electronics:
-Painless Performance Wiring Harness
-Custom Dakota Digital HDX-2014 Gauges
Dakota Digital Cruise Control
-Dakota Digital GPS with Remote Antenna and Ambient Air Temperature
-Vintage Air A/C Front and Rear
-Dakota Digital Climate Control
-iPad Mini 6 Dash
Digital Signal Processor
Backup Camera
-Dual Switch Pros SP-9100
Custom Digital Guard Dawg Keyless System
Speakers (JL Audio C2-650X?)
Two 12” Subwoofers
CB Radio
GMRS Radio
Rugged M1 Business Band Radio
110V Inverter
-Heavy-Duty Synchronized Electric Wipers
ARB On-Board Twin High Performance Air Compressor
-Power Locks and Windows
Tire Pressure Monitoring System
ARB Brushless Twin Compressor with Air Tank
Air Horn

Other Equipment:
AGM Jack

Wish List:
6R80 Billet 300M Input Shaft
Gen V Vintage Air Kit
Ported and Polished Heads
Callies Heat Treated Billet 4140 Main Caps
Callie’s Forged Ultra H-Beam Connecting Rods with H11 Bolts
4032 Forged Pistons
Jesel 4340 Billet Roller Rocker Arms
Scheel-Mann Vario F Klima Seats (Full Grain Brown Leather) Front and Rear

 

[hossbronco]

Here are some early photos.

 

[hossbronco]

Key Decisions:

7.3L Godzilla
I started this build looking at Coyotes, but decided on the 427W Stroker because I wanted more low-end torque. Mating it with the 6R80 presented some challenges, but the new Speed Gems adapter was promising. At the time, the 7.3L was just becoming available and was not much of a realistic option. It had not been put in any builds yet, lacked a controller, lacked aftermarket support, and little was known about its actual performance. Due to the lack of availability of parts in 2021, especially with regards to the Dart blocks, I had to wait a year and 3 months to receive the long block I had ordered. At that time, the prospects for a Godzilla build were looking much better. Controllers were available, with more coming out, enough aftermarket support was there to show the performance improvements that could be made with minor modifications, and the engine was actually cheaper than trying to build the 427W Stroker. I therefore sold the 427W long block and bought a base model 7.3L Godzilla. I'll be making the modifications myself. The Godzilla offers even more low-end torque, higher horsepower (with even a Whipple option), and modern diagnostics and reliability in a simple pushrod design. It will also bolt directly to my 6R80, eliminating the Speed Gems adapter and the 30 hp reduction caused by the 13 lb torque converter spacer.

Atlas Pro 3.0
I originally put money on an Atlas Pro 4 Speed 3.8 transfer case because I wanted to have something in the 80:1 range and something in the 65:1 range, in addition to being suitable for every terrain. I was very excited about the case but at some point realized that the planetary gears would multiply the input torque and potentially overpower the input shaft to the helical gears. At the encouragement of several experienced people I changed to the Atlas Pro 3.0 instead.

 

[ared77]

Sounds impressive! Good luck with your build.

Norm

 

[Yeller]

Watching and chiming in. Hopefully learning something and contributing when I can.

 

[hossbronco]

Thanks, y’all! I definitely value the input and will certainly make my fair share of mistakes. Nobody will learn more than me on this one, of course. If you think I’m making a mistake somewhere, tell me. I love the discussion and I have no problem being wrong, though I’ll certainly ask questions, and I’m sure there will be times I double down on a bad idea that we can all learn from.

Currently, the engine, transmission, transfer case, and fuel tank are all out. I’m going to pull the frame and have it blasted and painted while I wait for my engine to arrive. It’s been on order since April. Dart only recently started shipping blocks again.

 

[JB Fab]

My 2c... carefully calculate where your front driveline will be happy prior to "stretching" your front housing. Atlas clocked flat, 6R80 and a high-pinion front, you going to be threading a needle with your front driveline. Being able to position the the front pinion a couple inches one way or the other might save a whole bunch of hassle once your 3/4 of the way through the build......

Shown here is not flat, low pinion 4R100. Clearancing the tranny pan was necessary .

It complicated things since the front housing was pretty bulky, we had limited room to move it over (Note: cross-member was relocated forward during the next step).

 

[JB Fab]

Oh yeah... The Dart 427, being a tall deck block you are going to have clearance issues with the firewall and possibly the brake MC.
We modified the valve cover for clearance.

We relocated the MC all the way to the fender for additional clearance.

For reference: photo taken with 1.5" body spacers installed

 

[hossbronco]

It looks like you’ve got a pretty nice build there. I’ll be happy when RuffStuff starts making axle housings again.

The Dart block I’m getting is the 351 block bored to 4.125” with a 4” stroke. I don’t anticipate any firewall or MC clearance issues there. The Speed Gems adapter off the back of the engine might be a different issue, but BruiserOutdoors just test fit his with a 2” body lift and it cleared.

Driveshaft clearance is one of my bigger concerns, and the deeper pan and the added thickness of the Speed Gems adapter could only make the problem worse. I’m going to buy the axle tubes a little long so I can test fit and cut where I need to. I’m still on the fence about clocking the Atlas flat, as I’m a little nervous about cutting into the frame and possibly making it weaker there.

 

[Yeller]

As for cutting into the frame….. are you tying the cage and rockers to the frame? Thoughtfully done those items very effectively truss the frame to the point you could cut a section almost completely out without compromising anything.

 

[hossbronco]

Good point. Yes, I’m tying the cage and rock sliders to the frame, and I’ll certainly add some steel plating in the area as well. I was a little concerned with the 4-links connecting to the frame in the vicinity, not to mention the support for the transmission and transfer case, but I’m sure I can beef that area up enough to counter those forces. If only I still had access to SOLIDWORKS; I’d love to perform an FMEA on it.

 

[JB Fab]

Another note about the Dart block, you cant use any of the extreme-duty aftermarket engine mounts, you will need to use a stock mount that is modified, and you will need to do a bit of clearancing on the block webbing above the mount bolt bosses. really weird that you cant just bolt a stock mount on the block.

 

[hossbronco]

That’s disappointing. I already have a set of the WH Extreme Motor Mounts. I’d be curious to see what modifications I should make to stock mounts.

 

[hossbronco]

This isn’t a great photo, but I made the decision to use TBP’s Heavy Duty Wiper Arms (passenger side in photo). It took a while for the look to grow on me, but the springs are much stronger than other replacements I’ve tried, including the Cherokee wiper conversion. Also, I bought the WH Synchronized Electric Windshield Wiper Kit, and the Cherokee arms didn’t fit (they did fit on the original wiper linkage). I don’t think the driver’s side wiper, also from TBP, fit either, so my options were limited.

 

[DirtDonk]

I'm not exactly excited about the look of my new beam style 15" blades either. Looks kind of our of place on my old skinny arms, but I sure can't argue with how they work! Very happy about that.

That arm is pretty beefy looking. If it can hold any old blade hard against the window, it's a winner.
How long of a blade can you use with it?

paul

 

[hossbronco]

The blades are 12” and I don’t think they could be any longer. The arms are adjustable, but I have to have them all the way in to fit. if they were shorter I could probably get longer blades and better coverage. They’re the same width as the wiper arms on my wife’s former Expedition. The things I like are the springs are very heavy duty, they flip up, I think the blades could be replaced at any auto store, and the set screw makes them easy to remove. The down side to that is that if the set screw backs out the wipers will go flying. Here’s a photo with both installed with the blades. I wouldn’t be surprised if I switched back at some point.

 

[hossbronco]

This discussion has been good. I’m realizing I’m missing out on an additional 6” of wipers with these. The strong spring is nice, but not worth the trade off. I’ll have to figure out how to get other wiper arms to fit the splines on these motors.

 

[DirtDonk]

Are the arms adjustable for angle and length? They look to be, but also look like they're sucked in as far as they can go. Maybe like my original attempt the arms were just a bit too long. That's why I opted for the shortest version that Anco sold at the time. The longer ones were just too long.
Not sure which arms are on the '68, but they seem to be at least similar to the short Ancos and work out well.

Here's a pic of how they are currently sitting. I'm still working on the angle of the passenger side. I do like my blades angled down slightly when parked, rather than tucked up flat and tight against the top. But this one is hanging down farther than I like. However it sure does a full sweep!

The driver's side is better but because of the design of the system (custom electric linkage on early style frame) I do not get a full sweep of the driver's side. However, even with the slightly shortened sweep, the visibility is good and the wipe-ability of the blades is excellent!

Paul

 

[DirtDonk]

Sorry, you did mention adjustable and I just didn't remember. Been meaning to go look at Tom's description too but have not gotten 'roundtoityet.
I keep mentioning "Anco" in my posts, but though that's the brand on my '71, and these look almost identical, I really don't know what they are. But I can take measurements and look underneath at some point for any possible identifying numbers.
My older ones actually had smaller tips that required adapters to fit the standard blades. But these have the normal full width tips that snap right into a plethora of blade choices.
The "stems" or pivot points should be standard late model Bronco because that's the linkage that is in there to take the place of the original vacuum wipers.

I'll keep looking for a receipt for them in the stack to see if that will narrow it down. And I'm still going to experiment with angles and such.

Paul

 

[nvrstuk]

Great sounding build Hoss! I am familiar with a lot on your build and Jon was correct on watching out for clearance issues on the rear DS corner of the trans. I offset the center of the pinion closer to the DS frame rail than originally anticipated and it's tight.

The SpeedGems adapter should help you some with frt pinion angle if you're trying to go perfectly flat.

What adapter are you using btw the 6r & Procase?