This is the car that has monstered our Circuit Battle competition, has won many a Dutton tarmac rally against some of the meanest Porsches, Evos, STis and other GT-Rs and is now a Tsukuba veteran. This is Mark Berry and Russell Newman’s awesome R32 GT-R Skyline.
By the time you’re clicking through these pages, the Berry/Newman car will have gone to Japan and competed in what is surely the holy grail for lap sprinters around the world: a genuine time attack event at Tsukuba circuit, Japan. The event, known as the Rev Speed Time Attack, was held on December 5 (although this story was written shortly before it) and boasted a star-studded entry list that included JUN, HKS, Tomei, RE Amemiya and even two teams from the UK!
What had proven to be adept at monstering the competition in Australian motor sport was going up against some of the most carefully prepared, big dollar, multi-national corporation-backed juggernauts in a knock ‘em down, drag ‘em out battle royale. So, to present a firm challenge to this daunting field full of mechanical insanity, the boys had to take their road-going GT-R into full race specification.
We’re talking about a big dollar new engine that has been built from the ground up, new suspension, a thorough diet to reach a new target race weight and more. The whole car was gone through so that it would do Australia proud when it hit the frozen tarmac early in the Japanese winter and to present a real challenge to the rest of the world.
Taking an all-Australian developed car to the home of Time Attacks (and the Skyline) is a hugely ballsy move, because there is more than just Mark and Russell’s pride on the line. Japan is one of our local aftermarket’s burgeoning new marketplaces, so these guys had to be sure that their products would perform on-par (or better) than the world’s best, because any embarrassment could have major implications for the growth of their businesses.
Before the latest rebuild, the R32 retained most of its street car DNA, produced around 400kW in a responsive and torquey manner to suit circuit driving and ran a best of 10.02 seconds at 137mph on the drag strip. But, to compete against other cars that had been built from the ground-up with only the Time Attack regulations in mind, quite a few radical changes had to be undertaken, rendering the machine a race-only proposition.
Firstly, a race weight of 1300kg was deemed to be one of the main targets for the vehicle, and with much of the original bodywork still in place there were quite a few gains to be had. The interior was already gutted in preparation for the On Track Engineering Chromoly rollcage, while a custom-made carbon fibre boot lid and door cards from Carbon Components got the nod and new gutted carbon fibre door skins were fitted (saving some 24kg each!), plus Lexan windows to replace the heavy OEM glass.
Shedding those kilos helps the performance more than many would expect, with later braking points, higher corner speeds and better acceleration all possible through minimising fat on the car. On top of this, some racers have found that their cars use less fuel (as there is less mass to haul) and that they can then run lighter fuel loads, which helps weight even more.
Along with the roll cage, the chassis preparation also extended into getting the BNR32 corner-weighted, which is a massive amount of work but absolutely necessary to get the best out of the suspension set-up. It’s a technique that many touring car racing teams go through before each round, tailoring the handling for that particular circuit to suit the majority of the bends (either left or right) and something most other Time Attack teams do to eek out the merest of advantages over Tsukuba’s short distance.
Corner-weighting – and this is a simplification of the process – works off positioning the vehicle’s mass in the best location possible for braking and cornering and also managing energy transfer during that time. While negotiating a turn, weight will shift diagonally across a vehicle’s chassis, so in a right-hand bend the weight (and energy) will move from the left rear to the right front, causing issues with balance and grip (otherwise known as understeer and oversteer).
To remedy this, the car is put on scales and the mass of each corner is measured independently from the others and then the adjustments start to raise, lower, stiffen and soften different ends. However, changes made to one corner will affect the other three, as taking weight off the front left will also take weight off the right rear and place more weight on the opposite corners. Much like Old Man Newton said, for every action there is an equal and opposite reaction, so if weight is wound off struts on one diagonal axis, then the opposing axis needs to be stiffened by equal measure.
The coilovers being adjusted in question are nothing short of the Holy Grail for many tuners: hand-made remote canister Swedish Ohlins units bought through ex-pat Aussie Steve Bijok of Arabian Automotive Technologies in Dubai. Apart from being lighter in weight than a conventional coilover strut, the fluid-filled damper is kept cooler as there is more fluid available and the heat doesn’t get trapped in the body like it would on a normal unit. This means it is able to control compression and rebound forces more accurately as the oil is kept at its peak operating viscosity.
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