‘Think of it as a Porsche 911 that really “hauls”,’ reads GMC’s 1991 advert for this discreet-looking pick-up.Glitzy wheels and a subtly lower ride-height aside, it could have been the truck that ma or pa used to collect groceries from Fresh Pickens, just off Route 66.But the Porsche-shaming data running below would have shattered that quaint image faster than a moonshiner’s quarter-mile time.

GMC created a potent SUV pair that was ahead of its time with the Syclone (right) and Typhoon

The truck, called Syclone, could hit 60mph from rest in a claimed 4.6 secs (a 911 Carrera 4 took 5.2 secs), yet with nine times more cargo room than the Stuttgart car.And if anyone doubted the hype, they only had to read the September ’91 issue of Car and Driver, in which the $25,970 Syclone took to the drag strip next to a $122,180 Ferrari 348ts and beat it over the quarter-mile: 14.5 secs for the 348 to the Syclone’s 14.1 secs.Hell, it even outbraked the Ferrari from 70mph.

Mercury owned the ‘Cyclone’ name

Mesmerising though these figures were, on the face of it there was no sound reason to produce what was then termed ‘the world’s fastest truck’, along with its later SUV-bodied sibling, the Typhoon.But in the late 1980s, General Motors’ GMC (General Motors Company) brand was at the premium end of America’s truck market, at a time when the sector had just started to transition towards more leisure-orientated vehicles.The Syclone’s supercar-slaying acceleration made it a genuine pioneer, not only pre-dating other performance flatbeds, such as Ford’s F-150 Lightning and Dodge’s mighty Ram SRT-10, but also, arguably, the wider performance SUV market as we know it today.

Yet it was Buick, not GMC, that first inspired the Syclone.After retiring its Grand National performance model in 1987, the brand dropped one of its outgoing turbocharged 3.8-litre V6s into a Chevrolet S-10 pick-up.Hunkered down on lowered suspension and wearing wide, very un-truck-like alloys, it was touted to GM management and to Chevrolet as a range-topping ‘halo’ truck.

Fabric-trimmed bucket seats give the Syclone’s interior a purposeful look

The concept was initially rejected, but when GMC got wind of the project it immediately saw the potential, although not with the Grand National engine.Instead, GMC chose to retain the existing 4.3-litre Vortec V6 in its S-15 – the marque’s S-10 sibling – and uprate the unit to liberate even more giant-killing performance.All the same, when GM first presented the Syclone (Mercury owned the ‘Cyclone’ name, hence the spelling), along with a four-door GMC Jimmy-based vehicle called the Kalahari, under the ‘concept trucks’ banner at 1989’s Detroit show, the company had ‘no firm production plans’ for either, according to Autoweek.

The Syclone’s Mitsubishi-sourced turbocharger delivers up to 14psi of boost

At the time, the Syclone still used Buick’s blown 3.8 lump, whereas the Kalahari – later to become the Typhoon – had GM’s 4.3 V6.But by the time the pair reappeared at the New York International Automobile Show seven months later, the company line had changed to ‘not scheduled for production yet’ (Design News), hinting that both would become a reality.And that was reinforced when GMC took a modified S-15 to Bonneville and broke the Category E production speed record, with a 194.77mph flying mile.Suddenly, GMC had Ferrari and Porsche in its sights.

Sitting low on a set of 16in alloy rims, the Syclone certainly looks the part

You couldn’t fault its commitment to the performance cause.The problem was that developing such a niche offering in-house would have cost GM dear: $200million was mooted, along with a seven-year gestation before the Syclone reached showrooms.Fortunately, GMC product marketing man Kim Nielsen, who had driven the project from the start, had a trick up his sleeve.By outsourcing the engineering and manufacturing of everything that transformed a cooking S-15 into a Syclone, costs were brought down massively and the programme became viable.

‘The Syclone’s soundtrack is loud and proud’

Two companies – ASC McLaren and Production Automotive Services (PAS) – pitched for the work, but while ASC retained the stock S-15’s rear-drive transmission, PAS integrated the Chevrolet Astro Van’s four-wheel-drive system, complete with viscous centre differential.Given that both companies were proposing 280bhp and 350lb ft outputs, and the Syclone’s rear axle was carrying a mere 37% of the overall weight, rear-drive would only have achieved the biggest smokescreen ever.PAS won the contract, and at a sniff over $14million.

The firm, based in nearby Troy, Michigan, and collaborating with Nielsen, worked flat-out for the next 18 months to make sure the Syclone fulfilled the concept’s remit.To increase the Vortec engine’s outputs by 115bhp and 115lb ft, PAS added a Mitsubishi TD06-17C turbocharger running up to 14psi of boost, allied to a Garrett water-to-air intercooler.Lower-compression pistons were fitted, along with bespoke intake and exhaust manifolds.Larger throttle bodies were sourced from the Corvette parts bin, and a multi-point fuel-injection system was installed.

Both models share the 280bhp V6 powertrain and feature all-wheel drive

The Astro Van’s Borg-Warner transfer case delivered 65% of drive to the LSD-equipped rear axle and 35% to the front, so the potent turbocharged V6 could deploy all of its grunt without smoking most of it away.Underneath, the Syclone’s body-on-frame chassis was still suspended in traditional pick-up fashion: an independent front end with torsion bars, and a live rear axle with semi-elliptic leaf springs, but sitting lower than the standard S-15.Anti-lock braking (the Syclone was the first of its kind to carry the technology) was the only nod to chassis sophistication.But who cared about that on the drag strip?

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