Summary of this week’s magazine contents:
1) R35 GT-R Story
4 years after the GT-R Concept was shown, the base for the production car, the GT-R Proto, was shown to the public on October 19, 2005. Carlos Ghosn had announced at the 2003 Tokyo Motor Show that the GT-R would be “unveiled in 4 years on this stage” but did not give any details. So naturally, GT-R fans were left wondering whether the GT-R Concept was the design direction, and what kind of car the next GT-R would be.
So at the 39th Tokyo Motor Show – while the other concept cars had been unveiled, something on the center stage was still covered. So as the time for this car’s unveiling approached, the floor area became standing room only, and then the countdown began – “3, 2, 1, 0” – and as the white curtain was dropped, the GT-R Proto logo (which by the way uses font similar to the R34, as the R35 font had yet to be developed presumably) was readily apparent on the center of the black cloth covering a silver bodied car – which had unique vertical headlights that flashed on, much like a predator about to pounce on its prey.
“Wow it’s big…” was murmured in the crowd. And as the black cloth was lifted, everyone could see this car had a presence not felt with any Skyline GT-R.
Carlos Ghosn then takes the stage, and begins his speech, introducing the car “everyone’s been waiting for! The car Nissan promised that would deliver incredible driving pleasure, the GT-R Proto.” But he did not go into the car’s abilities or its specs. However one thing was obvious – the “gentlemen’s agreement” that mandated the 280 ps horsepower limit was clearly done away with, this was obvious by the car’s design.
2) Mechanism and Factory
The “Nissan Lateral Wet and Dry Sump System” – designed to maintain oil pressure despite the enormous side G forces!
It’s common knowledge that for high speed circuit runs, the oil that collects in the oil pan is bound to slosh to one side – and in a high performance car like the R35, with enormous acceleration, high deceleration due to its high performance brake system, and enormous side G forces – and in addition using a low viscosity oil (0W-40), proper oil management is essential.
Up until now, high performance domestic cars including the R32-R34 GT-Rs had to rely on baffles in their oil pans – both in the race cars and for road cars, by way of parts supplied by various tuners. The reason such baffles were needed however in the first place is that the oil extraction pipe was located in only location in the oil pan. When oil due to centrifugal force does not get taken up, in worst cases the engine can seize, and in the case of turbo cars, the turbine axles can suffer from a lack of lubrication.
In order to combat this, the VR38DETT has the “Nissan Lateral Wet and Dry Sump System.” A wet sump is used in most production cars – that is, as gravity pulls the oil down into the oil pan, it is then circulated by the oil pump. Simple, and cost effective, but not effective at preventing oil starvation in high G corners. On the other hand, a dry sump system uses two pumps and dedicated oil tank to effectively force the oil to circulate around – complex and costly, but used in race cars and luxury sports cars.
The GT-R system uses, in the middle of a standard oil pan (albeit one made of magnesium to reduce weight) on the same axis as the oil pump, a scavenger pump – so really a semi-dry sump system. The oil pan itself has on both left and right sides two oil returns each to ensure oil is continuously circulated.
3) Racing Legend
The Secrets behind the GT-R’s speed.
The Nissan GT-R, which made its race debut in 2008 at the Super GT series, was a revolutionary machine compared to Nissan’s own Z cars, and the SC430 and NSX of the competition, for the simple reason that from 2009, new regulations were to come into effect – and so it was not worth building a machine for the 2008 season, only to have to redesign for 2009. This article examines the workings of the 2008 GT-R race car.
A bit of background: the Super GT cars are based on road going models. When the series began as Group A, these race cars were touring cars with muscle. But as the regulations loosened, large changes were made. Until 2008, the rule was that the main monocoque frame of the base production car had to be utilized. However the front (in front of the firewall) and rears (behind the bulkhead) could be detached and new forms constructed on new subframes built on piping
However from 2009, the regulations changed – at minimum, the overall silhouette of the road going model had to be maintained. The roof and some outer panels had to be used, but everything else was allowed. At the same time, the drivetrains were unified to be rear wheel drive, with a 3.4 liter V-8 up front. The frames were allowed to be new monocoque designs made in carbon fiber.
So when the GT-R race cars were introduced in 2008 but under 2009 regulations, they were allowed to race under an exemption. And, the engines allowed were the 4.5 liter V-8 VK45DEs from the Zs and not the 3.4 liter V-8s. However these VK45DEs were outfitted with restrictors to limit horsepower, publicly quoted as “over 500hp.” But with such restrictors, they were able to obtain lots of low range torque.
While the roadgoing GT-R is 4WD with a rear transaxle, the Super GT cars are converted to rear wheel drive, use the same transmission and differentials from the Z race cars, mounted in the rear for optimal front/rear weight balance. Suspension design is given a free hand, allowing use of double wishbone suspensions as is found in most racing machines. In addition the use of inboard type dampers and springs allows for reducing unsprung weight, and brakes are AP Racing ventilated disks. Aerodynamics learned from the Z race cars are used, with the front and rear over-fenders designed especially to dissipate air.
4) How to Build
This week: Beginning to assemble the transaxle – attaching the oil pan plate and driveshafts.
Quote from Mizuno-san: “We have patented this independent type transaxle, Nissan’s own. This is the centerpiece of the GT-R’s Premium Midship Package. In addition to improving front rear weight distribution, it is a good layout for managing noise, vibration, and cooling of the powertrain.”
5) History of Nissan
This week: Datsun Truck Type 17 384
In contrast to the west, Japan’s car industry developed centered around commercial vehicles. With industrialization occurring rapidly in the 60 years from the Meiji Restoration to the 1930s, the Datsun Truck was a big success. In 1936, Datsun made more trucks (3601) than cars (2562). It should be noted that, in Japan the total number of cars made by all manufacturers did not surpass the total number of truck made until 1968.
In order to maximize cargo space, the cabin in the Datsun truck was moved forward. The first was the 13T in 1934, followed by the 14T, 15T, 16T and in 1937, the 17T. There was a corresponding progressive increase in load capacity, horsepower, powertrain and frame strength, and interior ventilation. Service and waranty procedures were solidified. The retail price of the 17T was 1930 yen.
Next Week – Attaching the two propeller shafts.