It wasn’t the only place the boys burned up serious amounts of cash and man-hours, though, as the former 400kW RB26DETT was stripped out and replaced with a new motor that has been infused with some of Australia’s most cutting edge performance modifications. Realistically, this new engine is probably more advanced than even the mighty Group A touring car-demolishing RB26s from Gibson Motorsport, though simply hanging a single (and massive) T88 or T51R turbocharger on the side of the in-line six, plugging in a PowerFC computer and screwing the sucker for all she was worth wasn’t going to cut the mustard for these boys, as it would have been useless to pack 10,000kW into a focused circuit car.
So, instead of setting a power target and finding the easiest way to that point, the boys focused on ensuring the car made whatever power it did in the best possible manner for circuit racing. This means a flat torque curve, stable power delivery, near-instantaneous response and an eagerness to rev among others, while the motor also had to be designed to withstand the high lateral loading during cornering (where the oil pushes to the outside edge of the sump) and longitudinal loading (where oil surges forward under brakes away from the pick-up).
Starting with a brand new, bare GT500 block was deemed to be the safest bet, as there might have been questions raised over the integrity of an older, used block when built with the sorts of fine tolerances that were required of this new powerlpant, not to mention the stresses from heat, power and high RPM it’d have to go through. Internally, the new rotating and reciprocating components were chosen for not only their strength but their balance as they would have to reliably endure the strains of 10,000rpm and provide good response.
To suit this requirement, a Tomei “full counter crankshaft” and H-beam connecting rods were installed, as the Japanese company have proven that this design will withstand over 1100 horsepower (800-plus kilowatts) and safely hit 10k on the tacho. Their crankshaft is a thing of beauty (and eye watering expense) with sharp-edged counterweights and two-way crank lubrication, on top of a manufacturing process in a climate controlled room that also has stringent check-off lists for quality control. A Ross Tuffbond harmonic balancer also assists in the motor staying together at those stratospheric speeds as it resists the natural twisting forces unloaded onto it, and maintains the ignition timing more accurately.
Though it provides a huge weight advantage, the Hi Octane Stage 4 dry sump oiling system also provided a huge boost in reliability and safety for the carefully assembled RB26DETT, with the oil temperatures post dry sump falling to 90-95 degrees from their previous 130 degree level, while coolant also running cooler which helps ensure the motor maintains a stable temperature and gets clean combustion. Part of the reason for the oil temperatures falling comes down to the extra capacity and fat lines that carry oil between the reservoir and motor, giving it time to radiate the heat into the air and other parts of the car.
All that work on the bottom end would have been wasted, though if nothing had been done with the top-end of the in-line six-pot as it simply would not have flowed enough air to reliably hit the RPM limit Mark and Russell were after. So, Tomei once again provided hardware to the tune of a pair of their lumpy camshafts, while Sydney’s own Hypertune whipped up a delicious new six-throttle plenum that replaces the stock individual throttle body unit with a more modern, more developed design.
On the exhaust side, Tomei dump pipes and a custom-made side-exit exhaust from CNJ Motorsport match the free-flowing nature of the RB26’s intake. Without these carefully selected pieces to assist the other side of the motor, there would still be massive amounts of restriction in the gas flow, which would lead to the engine struggling to hit 10,000 revolutions per-minute, straining itself and also wasting a lot of power.
The other piping on the motor comes courtesy of Trust and GReddy, who provided the intercooler and intake metalwork, which connects up to the twin GCG-modified 2860 turbochargers. As mentioned before, it would have been easy to make the car’s current power with a monster, over-over-sized snail, but it wouldn’t have provided the response and delivery that Russell and Mark were after. So, to this end the car’s huffers had to be carefully pieced together from a myriad of front and rear housing sizes and wheel trim options, as they all have a huge impact on spool times, power level and efficiency at various RPM points.
Other areas of the motor that were gone through include the fuel system, ignition and ECU, with a massive Turbosmart adjustable fuel pressure regulator, twin Bosch Motorsport pumps and 800cc Sard injectors taking up residence, while the fuel rail was customised so that fuel enters at both ends and exits in the middle, to ensure full flow and consistent supply to every injector at all times.
For the engine management, CNJ Motorsport set-up an Aussie-made Autronic SM2 ECU and plug-in loom, along with Autronic’s own CDI ignition module (which allows for more finely controlled ignition timing and stronger spark). The Autronic unit is a very advanced piece of work which allows three dimensional mapping of fuel and ignition, along with inputs for full-throttle shift options and traction and launch control, making it ideal for hard-tuned machinery set-up for circuit racing.
While the motor features quite radical modifications (for what started as a street car), the rest of the drivetrain is surprisingly mild, though this could be put down to the safe reliability of using tried-and-true methods and not risking experimental new technologies when the car has to run at Tsukuba in front of the rest of the world. Put simply, there is an NPC clutch and a five-speed gearbox filled with heavy duty PPGearbox innards, along with a lightweight carbon fibre tailshaft (to reduce rotating mass), a Cusco front differential to put power down more efficiently and Trust front and rear diff covers to aid cooling. Simple, but functional.
More Japanese components were used in the more detailed aspects of the car’s suspension to go along with those sexy Ohlins coilovers. Ikeya Formula, the renowned suspension arm specialist (and one of Editor Charles’ favourite tuning companies) are represented with a set of rear lower arms, while there are also Tein castor arms, flex-resisting “pineapple” cradle bushes and adjustable upper arms at both ends of the car. What they do, along with the coilovers, is provide huge scope for setting up the car’s wheel alignment, and therefore its braking, accelerative and cornering style. It means that a clued-up suspension workshop can tune the R32’s behaviour to such a fine point that it precisely matches what Mark and Russell want from it, and therefore can extract the fastest possible lap times in total comfort.
Those of you who’ve hung around the pits at racing circuits long enough will have heard the gnarled and grizzled old timers spit out the familiar line, “a race car is only as good as its brakes”. So, to ensure they had one of the best Mark and Russell picked up a set of English AP Racing brakes, arguably one of the best in the biz, with their six-piston calipers going on the front and four-piston jobbies in the rear, mated to some of AP’s massive multi-piece rotors to boot. Pagid pads and an AP Racing pedal box were also given the nod, with their impeccable track histories one of the shining highlights in the many reasons to spend the huge amounts of cash required to purchase this stuff.
Though you’d be forgiven for thinking this car is all function with nary a jot of care for form or styling, you couldn’t be further from the truth. Everything has been done with the highest quality of workmanship, and the styling aspect is very evident when you check out those delicious black 18x10.5-inch wheels RAYS Engineering TE37 lightweight rims, shod with super-fat 285mm-wide Dunlop 03G tyres. This is one mean, obsidian warrior that looks like its ready to tear your head off and feast on the goo inside at any time.
The detailing continues inside, where Russell and Mark could have just had the interior roughly gutted and left dirty, scratched and marked. However, the stripped and paired-back cabin has copped a professional spray job (along with the outside of the shell) after the On Track Engineering roll cage was put in, while there are expensive, hard-tuned signatures like a pair of fixed-back Recaro seats, a Stack instrument cluster and a full compliment of GReddy gauges.
So, will all this work be enough for the Aussie invasion of Japan’s most sacred of tuning battlegrounds? Only time will tell, though you’d have to feel a real sense of pride after seeing the quality of workmanship put into the Skyline. It’s arguably as fine as anything else you’d see short of a half-million-dollar corporate-back wunderpiece, and in some respects more amazing when you consider that two guys from Queensland started with a car only destined for mild tuning and a few track days. Even if they don’t shatter any lap records in some kind of Disney happy ending, the fact that they were invited to participate again our scene’s biggest guns is surely worth celebrating.
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