2002 Top Truck Challengers 1983 Chevy Blazer

Robert Bryce of Victoria, British Columbia, is a man of many talents. He's a Senior Programmer/ Analyst with a software firm, a Ph.D. candidate in computer science, a licensed steam-traction engineer, president of Extreme Axle Technology (Exaxt), and we'd be horribly remiss if we neglected to mention this-he's a two-time Central Canada fiddle champion. The guy must never sleep. On top of all this, Robert is a pretty darn good truck builder. As proof of that, his '83 Blazer is packed full of an eclectic variety of unusual mods designed for the two things that Top Truck requires-capability and durability.

Under the hood of the Blazer rests a 472ci Cadillac V-8 engine that's been heavily modified to run on propane. Modifications to the big Caddie include a Lunati camshaft and an Edelbrock Performer intake manifold. Other mods include a Mobi-Weld alternator, a pair of Optima Red Top batteries, 2 1/2-inch dual exhaust and Dynomax mufflers. The estimated 300 hp and 425 lb-ft of torque generated by the engine is routed through a modified TH400 transmission to an unusual but effective dual-transfer-case system that was designed by O.T.T. Industries. This system was devised to offset the 7.56:1 gearing of the Blazer's Unimog axles. It's composed of a reverse-mounted NP203 transfer case bolted to a twin-stick-equipped NP205 transfer case. While the crawl ratio of this system, at 80:1, isn't extreme, it creates a 0.5:1 Overdrive that allows Robert to cruise the truck at highway speeds while turning only 2,000 rpm. This system will come in handy in our acceleration tests, because without it, Robert says the truck would only be capable of a top speed of 40 mph. In case you're wondering, Robert says that operating the NP203 transfer case in reverse makes for a hotter running and noisier unit, but with the addition of tapered roller bearings on the idler shaft, he has had no problems with it.

An Exaxt crossover steering... 

   

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An Exaxt crossover steering system, Unimog axle and BDS 4-inch lift springs make up the front-end modifications. Robert abided by Canada's stringent vehicle modification laws in order to be street legal.

The power is transferred to the Unimog 404 axles via custom driveshafts. Both 'shafts use Ford 1-ton tubes and Toyota Land Cruiser ends at the differentials, but the rear uses a 1350 U-joint at the transfer case, while the front uses a 1330 CV joint at the transfer case. Robert chose this generation of Unimog axle because they use lighter axleshafts (less overall unsprung weight) and they feature cable-activated lockers. For enhanced stopping power, he added the Exaxt disc brake conversion kit to those 'Mog axles. The front axle is bolted to a 4-inch lift BDS leaf spring suspension with shackle reversal, while the rear axle is fastened to Ford F-150 leaf springs that have undergone a shackle flip. Single Rancho RS 9012 shocks dampen the trail bumps. The steering system was modified with a Pro Comp 4-inch drop pitman arm and an Exaxt crossover steering system. The truck rides on 44x18.5-16.5 Swampers on 16.5x8.75 Humvee bead lock rims.

The Blazer's body uses an '87 front clip and sits on a 3-inch lift. The exterior was stripped of all but the most important bolt-ons to ensure that it doesn't leave doo-dads strewn on tight trails. Inside the truck are a pair of Ford Aerostar seats, a slew of gauges (including monitors for temperatures in both transfer cases) and loads of spare parts.

It looks as though Robert has all the bases covered. Next month we'll see if it's enough to conquer the Challenge and its competitors.
-K.B.

The 472ci Cadillac V-8 engine...        read full caption The 472ci Cadillac V-8 engine pumping out 300hp on propane is backed by a TH400 transmission that was modified and assembled by Wayne Foster in Sooke, British Columbia. Other underhood mods include a Mobi-Weld alternator, dual Optima Red Top batteries and an engine-driven air compressor.

The rear Unimog axle carries...        read full caption The rear Unimog axle carries an Exaxt disc brake kit and cable-activated locker. It's suspended by Ford F-150 leaf springs that have undergone a shackle flip. Custom torque arms fight axle wrap. Robert can activate each rear disc brake independently by controlling electric solenoids from the cab which engage the hydraulic calipers to offer a significantly enhanced turning radius.

The cargo area of the Blazer...        read full caption The cargo area of the Blazer has been stripped of seating in favor of creating plenty of storage space for the spare tire, air tank, spare driveshafts, Hi-Lift jack and storage box.