Quinn Dusenberry designed and fabricated this three-link, coil-spring rear suspension to improve the axle articulation on his 1971 Bronco. The upper arm uses rubber bushings at the frame mounts and a chrome-moly rod end atop the 9-inch. The springs and mounts are from an early six-cylinder Bronco.
The rear coils are super soft, and Quinn uses two shocks per side to dampen unwanted suspension movement. Quinn wanted a full-length exhaust system but didn’t want undercarriage dragging problems, so he routed the tailpipes through the rear wheelwells--you can see where the tire rubs on full compression.
The rear axle is a strengthened Ford 9-inch with 4.11 gears and a factory limited-slip. Quinn plans to upgrade to 31-spline, large-bearing axles and a Detroit Locker.
All that rear axle movement has a downside. The relatively small 32x12.50-15 Swampers push the fender flares up on full compression. Quinn uses steel wheels, which he had powdercoated purple, for their rock-grinding strength.
The engine is a torquey 351 Windsor and the engine compartment is all business. If it wasn’t needed for ’wheeling, it was deleted.
Quinn grafted a Chevy power steering pump onto the Bronco to alleviate the typical Ford growling, squealing, and failures.
To help the Edelbrock carb run better at extreme angles, a Cagle fuel regulator was spliced into the feed line. The adjustable unit decreases fuel pressure as vacuum increases, thus lowering the fuel level in the bowl.
A Toyota power steering box from a two-wheel-drive truck was adapted to the frame and works fine with the Chevy pump and the Ford steering linkage through a custom pitman arm.
Ease of use and maintenance is now the interior decorating theme. Quinn reformed the floor to lower the seats 2 inches and moved them back 4 inches to give him more leg room. Then he painted everything Hammerite black.
Two ammo boxes have been welded to the floor to store small items, and a hand-operated emergency brake was scavenged from a Toyota Corolla to make it easier to get the rig rolling on a hill.
Quinn fabricated a custom tranny/transfer case tunnel to fit the NP435/Dana 20 combination. All of the vehicle’s electronics have been moved to the interior, some of which you can see.
The factory brake and clutch pedals were drilled, well, just because it looks cool. Slip-resistant pads were stuck on the pedals to make Quinns feet less likely to slip off when theyre covered with mud.
The battery and air locker compressor are mounted inside the cab. We’re not 100-percent sure that we’d do this, but it does make some repairs easy. There’s also a quick-disconnect fitting on the compressor for inflating tires.
Liquid-filled Auto Meter gauges keep tabs on the engine and fuel situation without bouncing the needles all over the place on rough terrain.
There are some things that all of us search for during a 4x4 buildup: traction, ground clearance, and axle articulation, to name a few. Starting with an early Bronco makes most of this easy to come by. But there just wasnt enough suspension movement in the back of his 1971 Bronco to satisfy Quinn Dusenberry, so he went to work fabricating his own coil-sprung three-link.
Quinn began his rear suspension work with radius arms and super-soft coil springs. He needed more control of the axlehousing, however, so he added a reverse wishbone with two connecting points on the frame and one on the top center of the axlehousing. This maintains pinion angle fairly well throughout suspension travel without limiting travel or axlehousing pivot.
The drivetrain in Quinn's tiger-striped purple Pony is just as different as the rear suspension. First, a stout 351W was built to produce tons of torque and run well in the diverse Northwest climates Quinn four-wheels in. The transmission is an NP435 and the T-case is a Dana 20 rebuilt by Olympic 4x4 in Snohomish, Washington. Quinn built an adapter to mate the two that he says is just like those the Bronco places sell, but $400 cheaper. With gobs of engine torque and low gears, Quinn does a lot of no-pedal 'wheeling, letting the truck just idle over obstacles. The rear is a reinforced 9-inch, while the front 44 uses an ARB Air-Locker to help the Bronco out of tight spots.
The interior is Spartan but fully functional. Late-model Toyota Camry seats were swapped in for comfort although the carpet was tossed for easy cleaning of the rig. The original gauges were ditched in favor of Auto Meter units. The exterior of Quinn's rig has been treated to a coat of Krylon Plum Safety Purple with black Hammerite tiger stripes. To keep some rain out, he fabricated a half-cab and painted it Hammerite silver for good measure.
As the accompanying photos show, there are tons of innovations all over Quinns Bronco. We think Quinn has gained yards in his search for inches on this cool trail rig.