Build Your Own R35, Week 18

by akasakaR33
5 years ago

Summary of this week’s contents:

1. R35 GT-R Story

Incremental improvements to performance – one year after release.

Mizuno-san had made the claim that the GT-R would be continuously improved. The first revision appeared in the 2008 model, released starting in April 2008, beginning with chassis number 004992. But the improvements were minor, and not enough to warrant being called even a “minor change” – these changes were limited to ride improvements, reduction in brake squeal, etc.

However the 2009 model, released on December 8, 2008, DID meet the “minor change” criteria, and hence the chassis numbers were reset to begin at 010001. First, due to more precise engine construction, power improved from 353kw (480ps) to 357kw (485ps). Torque also improved from 392Nm(40kgm) to 461Nm(47kgm). At the same time, even gas mileage improved from 8.2km/liter to 8.3km/liter.

Also, use of new shock absorbers, increase in the front spring rate, and revisions to the suspension setting were made. By using stiffer front control arm bushes, there was improved handling response as well as ride quality and stability.

Braking ability was improved by way of stiffer brake hoses. Visually, the Brembo only logo was changed to a Nissan logo on the calipers. Brilliant White Pearl was added as a new body color, and the Ultimate Metal Silver was improved by increased polishing which improved the color match between the body panels and the ABS bumpers. The front license plate holder was modified, reducing the car’s length by 5mm to 4650mm. The gas tank volume rose from 71liters to 74 liters.

Otherwise, there was a color change to Chrome Color Coat for the Rays alloy wheels, and the use of Dunlop tires was expanded.

While all these changes were impressive in a car that had only been on the market one year, the retail price also rose 10%. However, this did nothing to reduce demand for the car, despite the economic “Lehman Shock” which saw lower sales of all cars around the world.

While this was happening, Mizuno was preparing a special version car – the Spec V – which became Japan’s first car with standard carbon ceramic brakes, which was ultimately put on sale beginning January 8, 2010.

2. Mechanism & Factory

Making possible “machine gun shifting”

There are two clutches, one for odd numbered gears, one for even numbered gears. Each clutch has 6 plates, allowing for the GT-R’s high power.

During development the most important goal was to ensure F1 like super fast shift speed, and to be able to handle the power of the VR38DETT with no slippage – in order to give the driver direct and linear control.

During acceleration, each clutch is pre-engaged and ready. As soon as the driver pulls back on the shift lever, the released gear is replaced by the next engaged gear. The clutch itself is relatively compact, with 6 discs each for the odd and even gears – for a total of 12 – measuring 170mm across each. The older Skyline GT-Rs had only one clutch disc measuring 250mm. The reason the R35 clutches are smaller diameter is to reduce inertia, which slows shifting speeds – just like the F1 and Group C cars clutches with which Mizuno is familiar.

The clutch is a wet type, so even during idle there is no clutch noise. Most cars are dry type clutches which, when made multi plate, make noise. This also ensures the clutch’s longevity. While the parts are made with precision, after break-in the clutch is adjusted further –all of this ensuring the shift times of 0.2 seconds, the fastest in the world. This is the time between when the driver selects the gear and the time when the power reaches the rear wheels.

3. Racing Legend

The #1 Motul Car does the Pole-To-Win

Third race of the season was held at Fuji Speedway, and compared to the normal 300km, this race is longer at 500km. During qualifying, race driver Motoyama was able to get the best time.

During the race, the #1 continued to lead. However it was passed on the 9th lap by the #24 Kondo GT-R, but luckily, due to the flawless pit work by the Nismo race team, the first pit in and out allowed the #1 car to be in the lead again. However, it was passed by the #36 Lexus, but replacement driver Benoit kept the distance between the two cars to a minimum.

The race changed during the 2nd pit in. Again the flawless work of the Nismo team, allowed the #1 car to exit in front of the #36 car. Then, all Motoyama had to do was to keep the GT-R in first place.

As for the other GT-Rs, the #24 Kondo car showed stable driving and finished in 4th place. The #3 Hasemi Tomica GT-R finished in the same spot as it qualified, in 7th. The #12 IMPUL car had mechanical problems and was forced to retire.

4. How to Build

Rear Diffuser

Mizuno quote – The GT-R uses a rear diffuser made of carbon fiber – it generates downforce, and improves aerodynamics and high speed stability. It is also a shape that takes into consideration the cooling of the rear mounted transmission and differential.

Note, page 14 – describes how diffusers contribute to down force – while the GT-R does have spoilers to generate downforce over the rear wheels, the function of the lightweight carbon fiber rear diffuser (with the slim rear foglight) is to smooth out the flow of air under the car. In doing so, the air that is normally slower under the car, with the faster air over the car, which normally results in life, is reduced, allowing for a strong increase in downforce and high speed stability, and maintenance of high grip.

5. History of Nissan – 1947 Tama Truck Type EOT 47 II

After the war, there was a shortage of fuel. But with industry still recovering, lots of electricity was available for use. TAMA Automobile produced, in November 1946, the “EOT-46B” experimental electric truck, with motor built by Hitachi, and batteries by Yuasa. Then in April 1947, Tama produced the first production electric truck the EOT-47. A month later, a 4 person car version was introduced.

After this, Tama changed its name to Tokyo Electric Cars (Tokyo Denki Jidosha), and had 5 units roaming the streets of Tokyo. However, in 1950 with the advent of the Korean conflict, the lead used in the batteries exploded in price, such that the batteries cost 400,000-500,000 yen. At the same time, with gasoline becoming freely available due to the US Forces in Japan, the era of the electric car ended.

Next week: left rear disk rotor