GMC Syclone: Low-key, high-performance bargain

GMC brought out a factory hot rod in 1991 with its Syclone, but with only 2,995 built that model year, you may have not known about it, let alone seen one.

First things first: the spelling of the Syclone’s name. Since the model name “Cyclone” was already registered to Mercury, GMC changed the “C” to a “S” to get around using the name registered to another marque.

The Syclone was GMC’s “bad boy” truck with major-league muscle. It began with a 4.3-liter EFI Vortec V-6 in GMC’s compact S-15 pickup that it had rechristened the Sonoma for 1991. In building the Syclone, GMC had help from Production Automotive Services (PAS), Inc. an outside engineering firm in Troy, Mich., that had also helped General Motors’ Pontiac division build the 1989 Pontiac Turbo Trans Am.

Like the Turbo Trans Am, PAS put additional excitement under the Syclone’s hood by upgrading the truck with a liquid-intercooled Mitsubishi turbocharger with a 14-psi boost and 8.35:1 compression, pintel-style individual port fuel injectors, its own pistons and an oil cooler. All this magnified the punch of the 4.3-liter engine from the standard 160 hp to 280 hp. This herd of horsepower was channeled through a four-speed automatic transmission. At the time, it was said that this transmission was the only unit that worked with this engine setup. A dual-exhaust system produced a throaty rumble from the V-6.

Power to the pavement via the rear wheels could have been frisky, but the chassis also received upgrades including all-wheel drive. The Syclone’s suspension and brakes were also upgraded, so the boosted horsepower was only part of the equation. The Syclone had a sports-calibrated suspension that lowered the truck 2 inches, making its overall ground clearance just 6.25-inches. Torsion bars were located up front along with a stabilizer bar. Out back was a solid axle with semi-elliptic two-stage springs. The full-time all-wheel-drive system held the Syclone firmly planted to the ground. The transfer case was produced by Borg-Warner with 35 percent of torque going to the front and 65 percent going to the limited-slip rear axle. Disc brakes were in front with drums at the rear. The Syclone was the first production truck to come equipped with four-wheel anti-lock brakes. Blazing performance, the ability to stick to the road like glue, and being cat-like agile resulted in the Syclone rewriting the compact pickup rulebook.

Unlike most muscle cars from the ‘60s and early ’70s — and many trucks of its own era — the Syclone had many creature comforts. Included were power steering, brakes, windows and door locks. Other standard amenities were air conditioning, cruise control, tilt steering wheel, intermittent wipers and tinted glass. The only option was an AM/FM stereo cassette with a graphic equalizer.

The instrument cluster in front of the driver included three circular analog dials. The center speedometer registered up to 120 mph, and to its right was placed the tachometer with a turbo-boost gauge. The round circle to the left contained four gauges: at 12 o’clock was the fuel indicator, at 3 was the temperature gauge, at 6 was the battery charge and at 9 was the oil pressure gauge.

Contoured bucket seats were upholstered in black velour cloth with red lacing at the seams and “Syclone” stitched in red into the headrest. The seatbacks, however, were not adjustable. The center console had cup holders and a storage bin and also housed the automatic transmission gearshift. The steering wheel was leather-wrapped.

For such an uninhibited truck, the Syclone’s exterior surprisingly lacked a bold and vibrant appearance with splashy striping, which was in vogue during the period. All 1991 Syclones had an intimidating all-black exterior like the high-performance Buick Grand Nationals before them. Actually, the Syclone had a mono-chromatic two-tone paint scheme; while most of the body paint was a gloss black, the lower-body plastic cladding and ground effects were matte black. The tailgate and lower door trim had the tell-tale red “Syclone” nameplate with the standard-fare red GMC badge in the black grille. For ’92, other colors were available, but only three Syclones were built that year (a black GMC logo was on the three 1992 models, two of which survive with the third performing DOT crash-test duties).

Other outward appearance items on the 1991 Syclone were fog lamps, six-blade aluminum alloy wheels and a cargo box tonneau over the 6-foot bed. The latter was made by Lexxus Tru Cover. It clasped to an aluminum frame that connected to the bed without drilling holes.

Car and Driver compared a 1991 Ferrari 348ts costing $122,180 with a 1991 Syclone priced at $26,126 (the Syclone had the optional stereo equalizer). The Ferrari, priced at $96,060 more than GMC’s hot hauler, had 296 hp with 224 lbs-ft of torque mated to a five-speed manual. The Syclone had 280 hp with 350 lbs-ft of torque attached to a four-speed automatic 4L60 General Motors transmission. The Ferrari was lighter at 3,300 pounds while the Syclone was 3,600 pounds. Despite its greater weight, fewer horsepower and less-aerodynamic design, the Syclone sprinted to 30 mph in 1.6 seconds while the Ferrari took 2.0 seconds. And it didn’t get better for the Ferrari: the Syclone peeled away to 60 mph in 5.3 seconds while it took the Ferrari 6 seconds. The little devil’s blistering acceleration meant it completed the quarter mile in 14.1 seconds with the Ferrari right behind it in 14.5 seconds. However, the Italian sportster had a faster top speed, topping out at 166 mph while the Syclone hit a ceiling at 126 mph. Nevertheless, the Syclone had a more favorable dollar-to-fun ratio.

While the Syclone didn’t return to full production for 1992, its spirit lived on in the GMC Typhoon, a compact GMC Jimmy SUV modified by PAS with a drivetrain nearly identical to that of the Syclone. The Typhoon would be built for two years (1992 and 1993) with a combined production total of 4,697 performance SUVs for the two model years.

Today, a No. 3 Condition Syclones with around 50,000 miles fetch about $35,000 while low-mileage (around 10,000 miles) examples sell in the neighborhood of $50,000 — currently about the same as the 1991 Ferrari 348ts to which Car & Driver originally compared it.

Oddly, Typhoons in No. 3 Condition sell for less than Syclones (around $20,000), while low-mileage Typhoons sell for more than Syclones, making the Syclone still a bargain buy, especially with low-mileage. 

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