HKS R33 Drag GT-R – Groundbreaker – 124

July 12th, 2007 by NZPC

HKS R33 Drag GT-R

It was on October 22 2001 that the HKS R33 Drag GT-R ran its quickest ever zeroyon (0-400m) pass. At Sendai Hi-Land Raceway (a few hours’ drive north of Tokyo), driver Tetsuya Kawasaki pointed the purpose-built Nissan Skyline to a 7.67 @ 293kph pass. Not only had the car run a new personal best ET to reaffirm its status as 'the World’s Quickest 4WD’, but the record-setting blast would stand for five years before it was beaten. That happened in September 2006 at Willowbank Raceway in Queensland, Australia, when Kiwi driver Reece McGregor steered the NZ-built Heat Treatments Racing R32 GT-R to a blitzing 7.57 @ 306kph. “Over the past few years many have tried to better what HKS achieved with its R33 Drag GT-R, but only one team has achieved the goal. Respect to one of the greatest import racecars ever built.”

In a surreal moment, amidst a barrage of shotgun-like backfires the HKS R33 Drag GT-R froze momentarily. Poised delicately on the staging beam, flames belched from its dual side-exiting exhaust. The tree lights dropped and well over 1000PS worth of hard-tuned RB26 might was unleashed towards all four wheels. There was no big squat, just slingshot-like velocity, interrupted only by a few 'hops’ as the suspension found its groove on the sticky, sweet surface. The world’s quickest four-wheel drive disappeared into the fading twilight, each air-assisted gearshift sending another flame to illuminate the strip-side barriers. A mere 7.8 seconds later the ’chute was deployed and the run was over. The Skyline hadn’t eclipsed its own record set six months earlier, but no one in the awestruck crowd was complaining.

Given the car’s hasty retirement just a couple of weeks out from its race date with Reece McGregor and the Heat Treatments Racing team, I guess I can count myself very lucky. At the time, witnessing the car run at Willowbank Raceway in Queensland, Australia, was unlike anything I had seen before. Five years on we meet again. It’s night and we’re at Auckland’s Redline Performance to take a crawl over the car regarded as one of import drag racing’s most influential. The Skyline had come directly from Thailand, where it had raced in November last year.

Like an ageing athlete, though, the former world champ had run well off the pace at Bangkok’s infamous Drag Avenue. It seemed like age had finally caught up with the car engineered by HKS specifically for zeroyon (0-400m) duties almost a decadeago, and the cracks were beginning to show. But it wasn’t always like this.

At Japan’s Sendai Hi-Land Raceway in October 2001, HKS driver Tetsuya Kawasaki had pointed the Nissan to an incomprehensible 7.67 ET. Back then no other 4WD car on the planet had covered the quarter mile quicker. To achieve this, HKS had to break ground. At the time, drag racing still enjoyed a strong following in Japan, but racing a 4WD machine at thislevel was something new and the team was heading into uncharted territory.

The project itself had two-fold appeal for HKS. On one hand it would help HKS president Hiroyuki
Hasegawa achieve his racing goals; and on the other, the company would benefit from a real-time test bed in the design and manufacture of new performance products. Almost a decade after it all started, the result of all that hard work is still impressive.

Lifting the lightweight carbon fibre bonnet was a rare treat. Beneath it sat the result of an extensive R&D programme led by HKS Motorsport in the mid-to-late ’90s. While standard-issue RB26 engines have a solid reputation for their ability to achieve serious power levels without going to too much effort, creating a monster with more than four-and-a-half times the intended output had required a little more forward thinking. For drag racing, the Skyline’s engine features countless strengthening and power-making components — many of which were engineered by HKS specifically for the application.

It starts in the bottom end where, deep within the blue-printed Nismo N1 block, an HKS custom (SPL)

billet crankshaft pushes HKS Step-3 H-beam connecting rods and a bank of Step-3 87mm forged pistons. Not only was the gear fitted to withstand high boost and high RPM levels, but also to push the straight six’s cubic capacity out to 2771cc. HKS was never going to realise the performance potential of a serious forced induction setup unless the enginewas up to flowing the numbers. As such, much of the engine’s power is made in the RB’s DOHC 24v cylinder head, which underwent a significant amount of race prep work on HKS Motorsport’s flow bench.

Along with port and polish work, the head features huge HKS Step-Pro valves and a pair of high-lift Step-Pro camshafts spun by HKS slide pulleys. On an HKS Racing SPL exhaust manifold sits an angled pair of Garrett GT-series turbochargers uniquely engineered to HKS Motorsport specifications. Each runs a single HKS Racing SPL external wastegate venting to the atmosphere, and there are two 4-inch exhaust pipes exiting under the passenger side door. On the other side of the engine, it’s the giant, front-mounted HKS GT intercooler providing the engine with chilled air through a 95mm throttle body.

At full noise, as much as 35psi worth of the good stuff would have been force-fed into the aluminium HKS Racing SPL plenum chamber. With the intake manifold titled for optimum flow into the cylinder head, it’s here that the HKS Drag Gas fuel supplied from a trio of Bosch Motorsport pumps and a tiny boot-mounted fuel cell is injected. The setup runs twin adjustable HKS fuel rails and a total of one dozen 550cc injectors. An HKS Twin Power system was employed to amplify the spark, with fuel and ignition mapping run through an HKS F-CON V Pro engine management system. At last count the engine produced an impressive 1300PS @ 9000rpm, and generated 110kg/m @ 6500rpm.

Lifting the lightweight carbon fibre bonnet was a rare treat. Beneath it sat the result of an extensive R&D programme led by HKS Motorsport in the mid-to-late ’90s.

While the Drag GT-R always ran a 5-speed sequential gearbox, in its final tune it made use of an air-assisted shifting mechanism.

That meant that although the car still had its traditional shifter, gear changes were instead made through the press of a button on the steering wheel. The transmission utilises an HKS Racing SPL 4-plate clutch, with drive running though a pair of SPL differentials.

Looking under the car revealed a few more insights into some of the development work that went into this car. As expected, there were things like custom mounts for the gearbox, and alongside the HKS Super Racing springs, there was plenty of other suspension work.

On closer inspection it seemed that some pretty clever engineering had gone on inside HKS Motorsport. The most significant had been the raising of the front and rear sub-frames, a modification that allowed the body to actually sit a lot lower than it normally would. In doing this, though, the firewall had to be removed and a new one created. The fit of the custom vented bonnet also hints at the higher positioning of the engine.

Power and driveline aside, the other key factor in the success of this car was its weight — or more importantly the lack of it. We’re unsure of how much it actually tips the scales at, but pushing it around for the photoshoot we’re guessing not a hell of a lot.

Surprisingly though, much of the original bodywork remains, and apart from the doors, the boot-lid, the hood and the windows, it’s pretty much all original pressed steel and aluminium fare. Not including the modified plastic bumpers, the material of choice for almost everything else on the car was carbon fibre, which as we all know is both strong and light.

The doors are a perfect example of the extremes HKS went to in chasing weight reduction. There’s little structure to them, and only a thin carbon skin holding them together, while Lexan made a light replacement for heavy glass.

In the boot a carbon panel replaces the floor, and most of the framework has been drilled in an effort to shed precious grams. Even the tail-lights have been modified, so only the outer plastic lens remains.

Look inside the cockpit and there’s further evidence of HKS Motorsport’s 'less is more’ philosophy. Carbon fibre panelling has replaced everything plastic, and the roll-cage appears to be of a frighteningly minimalist design. Strapped into a Bride carbon/ kevlar racing seat, Kawasaki obviously had a lot of faith in the car and his driving. For sub eight-second passes, only four instruments were deemed necessary: an Auto Meter brake pressure gauge, an Auto Meter Pro-Light shift light, a digital gear position display and an HKS oil pressure meter.

Through an HKS Torque Split Converter, Kawasaki would switch the GT-R into 2WD mode for the burn-out, and back into 4WD for the launch and run. This was achieved with the help of two brake buttons on the steering wheel: one for the front brakes and one for the rear. For the burnout, Kawasaki would lock the front brakes, jump on the gas and pull the car through three gears before releasing the button and laying two black rubber lines to run on. At launch, the engine could be held in first gear on the limiter and the brakes released when the Christmas tree lights dropped.

By all accounts it’s a pretty straightforward set up, but one that certainly did its job. I think the most impressive aspect of the car is that in engineering it, HKS had no one to look to and no proven record to chase. It’s now clear that the ET achieved back in 2001 was as far as the technology was going to take it — and that’s a pretty amazing feat.

Over the past few years many have tried to better what HKS achieved with its R33 Drag GT-R, but only one team has achieved the goal. Respect to one of the greatest import racecars ever built.

TUNING MENU

HKS R33 DRAG GT24V

Engine: 9.8:1 compression ratio, HKS Step-3 87mm forged pistons, HKS Step-3 H-beam connecting rods, HKS Step-3 billet crankshaft, HKS Racing SPL cylinder head, HKS Step-Pro camshafts, HKS aluminium slide cam gears, HKS Step-Pro valves, 2x HKS GT-Series turbochargers, 2x HKS Racing SPL wastegates, HKS GT intercooler, HKS Racing SPL piping, HKS Racing SPL extractor manifold, HKS Racing SPL exhaust system, HKS Racing SPL plenum, 6x 550cc primary injectors, 6x 550cc secondary injectors, Harwood 5L fuel cell, 3x Bosch Motorsport fuel pumps, HKS Super Fire Racing Pro spark plugs, HKS F-CON V Pro engine management system, HKS EVC boost controller, HKS Torque Split Converter, NGK L-Meter

Driveline: HKS 5-speed air-shifted sequential gearbox, Cliffon air tank, HKS Racing SPL 4-plate clutch, HKS Racing SPL differentials

Suspension/Brakes: HKS Racing SPL Hipermax Drag adjustable shock absorbers, HKS Super Racing springs (front 4kg, rear 3kg), AP Racing rotors/callipers front/rear

Exterior:
Factory front bumper, rear bumper, front guards, quarter panels and roof, HKS SPL car bon fibre bonnet, HKS SPL carbon fibre grille, HKS SPL carbon fibre headlight intake, HKS SPL carbon fibre doors, HKS SPL carbon fibre boot, HKS SPL aluminium/carbon boot spoiler, HKS SPL rear carbon diffuser, Lexan windows, Deist parachute

Interior:
HKS SPL carbon fibre panels, multi- point rollcage, Bride carbon fibre seat, Sabelt 4-point harness belt, HKS oil pressure meter, Auto Meter brake pressure meter, Auto Meter Pro-Lite shift light, Espec Thermo Recorder, Lifeline fire extinguisher system

Wheels/Tyres: 15×8-inch Bogart Drag-On Star wheels front/rear, Goodyear Eagle Dragway Special tyres — 28.0×10-15 front, 28.0×11-15 rear

Performance:
Dyno Power — 1300PS @ 9000rpm, Dyno Torque —110kg/m @ 6500rpm, Maximum Boost — 2.4kg/cm (35psi), 0-400m — 7.67 @ 293kph (Sendai Hi-Land Raceway, Japan — Oct 2001)