GT-R Nismo Z-Tune: Remembering the Ultimate Street-Legal Skyline

However, that's not where the R34's story ends, as the Japanese manufacturer had a massive surprise for its fans.

About a year and a half after production of the R34 GT-R ended, Nissan announced that it had given Nismo the go-ahead to launch a limited series of the mighty Z-tune.

Over the next three and a half years, the Japanese carmaker's motorsport and high-performance division put together twenty examples of what became the ultimate road-legal, Skyline-based GT-R.

It started as a wild concept car

The Z-tune's story actually starts in the year 2000 at the foothills of the breathtaking Mount Fuji.

On November 26, during the Nismo festival held at the famous Fuji Speedway, Nissan's division unveiled a one-off R34 GT-R.

Donning a bespoke body kit and a comprehensively tuned, 600-hp, 2.8-liter version of the stock RB inline-six, the incredible machine sent fans into a frenzy and won the festival's Tuners' Battle contest.

A limited series based on used R34 GT-Rs

Though Nismo initially announced that it had no plans to produce the wild concept, a select team of the division's finest began working on a production version shortly after the festival ended.

Aiming to deliver the ultimate road-legal GT-R, Nismo spent the next three years developing and testing the car.

But, by the time Nissan approved their project in late 2003, the R34's production was over.

To build the 20 units of the Z-tune GT-R, Nismo began hunting down used JDM V-spec GT-Rs with less than 18,641 miles (30,000 km) on the odometer.

Based on a drastically improved chassis

The project was kept secret until 2005 when, as part of Nismo's 20th anniversary celebrations, fans were announced that the Z-tune would be produced in a limited series of 20 examples.

Several used GT-Rs had already been given a comprehensive makeover by this time and were ready to hit the streets in Z-tune guise.

All donor cars were delivered to Nismo's Omori facility, stripped down to the bare chassis, and thoroughly enhanced.

After each chassis had its paint and was thoroughly inspected, the Nismo team upgraded it with CFRP (carbon fiber-reinforced polymer) reinforcements.

Additionally, the suspension system was improved with three-way adjustable racing shocks, beefier anti-roll bars, stiffer bushings, and recalibrated geometry.

Stopping power was also taken to another level. The standard brakes, which consisted of four-piston calipers in the front and two-piston units at the rear, were swapped with six-piston (front) and four-piston (rear) calipers that hugged larger-diameter discs - all made by Brembo.

Body and interior improvements galore

Apart from the chassis tuning, each Z-tune received several bespoke body panels meant to improve looks and aerodynamics.

These upgrades included new bumpers, front fenders, a hood with five huge vents inspired by the GT500 R34 race car, subtly flared rear wheel arches, and a rear spoiler flap - all fabricated from CFRP.

Inside, the production of Z-tune differed greatly from the original concept. Designed to offer more comfort and an upscale feel, the cabin received Alcantara and leather upholstery that was finished in black and red.

Other bespoke interior upgrades included a new Nissan-branded steering wheel, white gauges with an 11,000-rpm tach, and a 320-kph (199 mph) speedometer, as well as a titanium shifter.

Powered by a straight-six on steroids

The production Z-tune's heart was based on the initial concept car's Z1-spec inline six, which in turn was based on a combination of the stock RB26DETT and GT500 race engine.

Codenamed Z2, the engine was built around a reinforced cast iron block derived from Nismo's GT500 race program.

With an enlarged cylinder bore and stroke, the six-cylinder displaced 2.8 liters and featured a wide range of upgrades like a GT500-derived crankshaft, stronger conrods, lighter forged pistons, hotter cams, a high-flow fuel injection system, and new cylinder heads with improved combustion chamber design.

Moreover, the Z2 received a new intake, a revised, heavy-duty cooling system, and a pair of IHI turbochargers specifically developed for the Z-tune.

Assembled by hand, the astonishing engine could easily make 500 hp at 6,800 rpm. When the tach needle reached 5,200 rpm, the six-cylinder also sent 398 lb-ft (540 Nm) of twist to all four wheels through a Getrag six-speed manual, a carbon fiber driveshaft, and a pair of limited-slip diffs.

An iconic supercar slayer

Though it was equipped with a multitude of CFRP components, the Z-tune ended up being about 88 pounds (40 kg) heavier than the original R34 GT-R.

However, with the Z2-spec engine making nearly double the power, the Z-tune could accelerate to 62 mph (100kph) in 3.8 seconds, which made it quicker than a V10-powered Lamborghini Gallardo.

Even more impressive, the car's listed top speed now stood at 203 mph (326 kph), meaning that Z-tune was also theoretically faster than the Gallardo and even the original Murcielago - albeit that figure was never officially put to the test.

Apart from the prototype, Nismo built the remaining 19 units from 2005 to 2007. Except for one, all received a custom paint dubbed Z-tune Silver. The sole exception was tailor-made for a special (yet unnamed) client who wanted his example finished in Midnight Purple.

You can watch how this unique Z-tune receives a premium detailing treatment in the YouTube video below by Hartnett Media.

While the standard R34 Skyline GT-R is one of the most iconic and sought-after sports cars ever built, the limited edition Z-tune managed to take it to another level, and for many enthusiasts, it remains the greatest Nismo-engineered car ever unleashed on public roads.