Mark McCarthy's 1970 BroncoClick here for the full gallery of project photos!
Mark spends most of his off-time in the remote areas of Baja exploring in his Bronco, chasing at desert races and speeding across the desert penninsula. He wanted his Bronco to be up to the task, able to soak up the rough terrain at speed, providing a comfortable ride and aggressive performance. So he brought it to West Coast Broncos for the first of several phases in building his idea of the ultimate desert Bronco.
Mark already had a set of WCB's signature pre-runner fiberglass fender flares, so we set out to fill them up with tires and travel. In order to provide ultimate stability at higher speeds and improved driveshaft angles for increased travel, we located a full width high pinion Dana 44 out of a 78/79 Bronco and proceeded to shoe-horn it into Mark's Bronco. There are several routes you can take when installing a full width Dana 44. Earlier models of this axle featured welded-on C-bushing wedges which can be moved inboard to the Early Bronco's stock spring bucket dimensions (as we did with Andrew's '75 Bronco, also featured in these Project pages). 78/79 Dana 44's such as the one we chose for Mark's full-width swap feature a "cast" C-bushing wedge that is integrated into the steering knuckle casting, and therefore impossible to move. Because these axles are more readily available, WCB has developed a procedure for installing them into the Early Bronco which involves moving the coil spring buckets 2" outboard of the frame to align them with the C-bushing weges on the axle.
This strategy for doing a full-width swap is advantageous for certain kinds of off-road use. Landing the springs further outboard on the axle provides better anti-sway control, which can be a benefit especially in higher-speed uses. West Coast Broncos has performed many full-width swaps here at our shop using this method, but in custom one-off builds. Thick steel plate is used to fabricate a stand-off, or spacer, to locate the coil spring bucket 2" away from the frame rail. Look for WCB to offer a Do-It-Yourself full width kit with pre-fabricated brackets in the near future.
There are many added benefits to using the 78/79 Dana 44 in the Early Bronco, even beyond the merits of its full width and high pinion. You also get the coveted "Ford" disk brakes, featuring 5-bolt spindles with large bores in the knuckles for installing and removing (sometimes damaged) axles with larger 760-size u-joints. And of course the axles and u-joints themselves are an upgrade over the Early Bronco units. Mark's Dana 44 wasn't just pulled out of the junk pile and thrown under his rig, it underwent a complete rebuild including all new ball joints, u-joints, bearings, seals, rotors, calipers and caliper lines. The housing itself was buffed and painted like new, as were the knuckles and caliper brackets. We capped the housing off with WCB's Extreme Duty Dana 44 Diff Cover to protect the ring gear from those boulders that tend to jump into your path when you're hauling ass through the sand washes.
A complete new suspension package was also in order. West Coast Broncos long travel tubular radius arms were installed along with new Deaver coils and leaf springs. To provide effective spring damping for those long sections of rough Baja terrain, we fabricated a custom tubular shock mounting system to house massive King 3" bypass shocks. Each shock hoop is braced to the frame in three places, as well as a beefy cross-over brace to tie the hoops together for an even more rigid structure. To provide soft landings over the jumps we installed a pair of King 2.5" hydraulic bumpstops in custom mounts, and fabricated landing pads onto the WCB radius arms below.
To provide accurate, reliable steering without binding through the increased suspension travel, we fabricated a heavy duty tie rod and drag link using thick wall DOM tubing and heim joints. The drag link and track bar were installed together for optimum steering geometry. Great care was taken to ensure the best steering performance at speed, and our initial testing revealed a complete absence of bumpsteer through suspension travel. That same testing, by the way, yielded great results for the entire full width axle conversion and suspension fabrication. This truck is now truly awesome to drive at speed, soaking up the rough stuff in a manner uncommon to typical short wheelbase trucks.
This was just the first phase of Mark's buildup at WCB. Future projects may include a rear suspension system that is comensurate with the front, a custom cage, drivetrain modifications and more.
© 2008 WEST COAST BRONCOS, INC.