If you’re the proud owner of an iconic Japanese performance car and a Speedhunters reader, I’m going to bet that it wasn’t the model’s factory performance and aesthetics that initially sparked your interest in it.

I’d say, the original attraction was more likely born from the JDM aftermarket and the tuning methodology it applied to domestic cars through the celebrated ’90s and early ’00s era.

Of course, there are always exceptions to the rule, but the notion of what a JDM performance car could be as opposed to how it rolled off the production line (more than often in a de-tuned manner, remember) was the ownership inspiration for many. It was certainly true of my friend group as we grew up around relatively cheap and plentiful used Japanese imports here in New Zealand. Aftermarket modifications performed by Japanese tuning masters made these cars.

But if tuned cars are the ones originally lusted over, why is it that the most sought after performance cars from the JDM golden era are all of a sudden the stock, or restored as such, ones?

If you can look past the - groan - ‘investment’ potential, there’s another big reason. We’ve all seen cheap and nasty modifications and low-rent mechanical work applied to these platforms over the years, and many of these ‘upgrades’ can’t be undone easily or economically. So in that respect, there’s a lot of appeal in a car that hasn’t been mucked about with. But I don’t think there are many people paying big money for stock JDM performance cars just so they can be the first ones to modify them. Those cars are likely to be kept stock.

There’s nothing wrong with this; I love seeing original and mint-restored 30-year-old JDM performance icons as much as the next enthusiast. From an ownership perspective though, they don’t really interest me. I grew up dreaming of HKS T51R Kai turbochargers, OS-88 6-speed sequential gearboxes, RAYS Volk Racing TE37 wheels, Bride seats and blue Cusco bolt-in ‘roll cages’ that bent around the dashboard (yikes), and seeing these things and other period (and modern) modifications in use on cars that would be worth more without them always puts a smile on my face.

Sadly though, these cars will only become fewer and farther between. If time (read: rust, mileage, theft, dodgy mechanics, inexperienced and overconfident drivers etc.) wasn’t a big enough factor to their extinction, the fact that the most sought after parts for many JDM performance machines are now OEM ones should tell you all you need to know…

But thankfully, there are still plenty of people who see the cultural and physical value in modified cars, and earlier in the month Dino gave us a look at a BNR32 Skyline GT-R owned by one such individual. That particular car was purchased in Japan for its UK-based owner, but then fully modified by Midori Seibi Center in Yokohama (and others). It left Japan with a dream list of upgrades, including a full engine build good for 500+hp centred around an N1 block and featuring Tomei turbos, plus RAYS Volk Racing TE37V wheels and a full Robson Leather interior.

As far as privately-owned Skyline GT-R road cars go, the build ticks so many boxes that Dino ended his story by asking what more could be done to improve it.

But what’s possible when a tuning company itself lets loose with an unlimited budget? You get a build like the Sun Line Racing BNR34, another modified-in-Japan Skyline that found a new home in the United Kingdom, this time via Harlow Jap Autos back in 2018.

In the Skyline GT-R tuning world, Sun Line Racing (SLR) definitely needs no introduction; the Okayama-based shop’s reputation for building hardcore track weapons with an ultra-high attention to detail precedes them. But with this BNR34 demo machine, they took all of their race-car-building knowhow and applied it to a street car.

That’s not to say it was watered down though; the engine produced 720PS on 1.5bar (22psi) of boost pressure, and it managed sub-1-minute lap times around Tsukuba Circuit in full road-going trim. As far as tuned R34 GT-Rs go, this one remains absolute royalty, many years after being built and 10+ years completely off the radar before HJA found it.

With a reputed build cost of ¥15million (approximately US$130K) over and above the car’s initial purchase cost, you can be sure that no stone was left unturned by Sun Line Racing in its creation. You’ll find its full list of modifications at the end of this feature, but let’s look at some of the highlights…

Outside, carbon fibre is in no short supply. The composite material was used for the bonnet, fenders, boot and GT wing blade – and it was all made in-house at SLR. C-West provided the carbon front bumper (with carbon canards) and Craft Square the carbon mirrors.

The centrepiece of the Sun Line R34 is its full N1 engine-based build. SLR chose HKS’s 2.8L stroker kit to increase capacity and strength, and then made the most of it with HKS’s V-CAM system in a fully race-prepped cylinder head, a giant Trust T88-34D turbocharger, HPI front-mount intercooler, Nismo plenum, Sard 800cc injectors and custom SLR titanium down-pipe and exhaust among many other upgrades. Final tuning was made via an HKS F-CON V Pro engine management system.

Power finds its way to the ground through a Holinger Engineering 6-speed sequential gearbox, Exedy Racing triple-plate clutch, ATS carbon front LSD and OS Giken rear diff.

For suspension, every arm and rod that could be replaced was done so with adjustable SLR items. The coilovers are even Sun Line Racing’s own specification. For brakes, an Endless 6-pot calliper/370mm rotor front package and 4-pot/332mm rear setup ensures the Skyline has no problem slowing down from hyper-speed.

As it was built as a road car first and foremost, and despite what the race-ready exterior says, you won’t find a stripped interior inside this R34. Yes, there’s a roll cage, but it’s been neatly integrated so as not to limit entry and exit in any way. SLR chose Bride Gias carbon reclining buckets for the front seating, a classic Nardi steering, Nismo meters, and added their own custom dry carbon door panels.

For me, this is the sort of GT-R that made all GT-Rs the revered machines they are today – not a new auction record for a stock example.

Whether lightly tweaked or hard tuned, long live modified Japanese cars.

Brad Lord
Instagram: speedhunters_brad
brad@speedhunters.com

Photography by Mark Riccioni
Instagram: mark_scenemedia
Twitter: markriccioni
mark@speedhunters.com

Sun Line Racing 1999 Nissan Skyline GT-R (BNR34)

Engine: N1 block, HKS 2.8 stroker kit – HKS 87mm forged pistons, HKS H-section forged connecting rods, HKS forged lightweight full-counter crank, Trust large capacity sump extension, Tomei head & crank studs/bolts, Tomei bearings, Tomei oil pump, Tomei timing belt, Tomei 1.5mm head gasket, HKS V-CAM Step Pro system, Tomei 270deg/10.5mm exhaust cam, Tomei adjustable cam gear, Tomei Type B valve springs, Tomei valve lifters, N1 cylinder head, cylinder head processing, head surface correction, new polished valves, race-grade valve guides, water jacket processing, enlarged ports, Trust T88H-34D turbocharger, Trust exhaust manifold, Trust external wastegate, Trust Type R blow-off valve, SLR custom Titan 100mm front pipe, SLR custom Titan 100mm exhaust, HKS air intake, SLR custom titanium exhaust, SLR custom titanium down-pipe, Nismo plenum, SLR titanium intake piping, SLR hydro-dipped engine covers, Naprec throttle body processing, intake manifold internally enlarged, Mine’s cam baffles, N1 water pump, SLR catch tank, Samco coolant hoses, SLR GT radiator Type R, SLR radiator cooling panel, SLR coolant expansion tank, Trust oil cooler kit, Billion thermostat, HPI intercooler, Tomei fuel rail, Sard 800cc fuel injectors, Sard fuel pressure regulator, SLR collector tank, lightweight Teflon fuel lines, HKS in-tank fuel pump, 2x Bosch 044 fuel pumps, metal fuel lines, HKS F-CON V Pro, HKS V-CAM controller, Blitz Dual-SBC boost controlle, Field ETS torque split controller

Drivetrain: Holinger Engineering 6-speed sequential transmission, electronic gear indicator, Exedy triple-plate clutch, ATS front carbon LSD, Trust large-capacity front diff cover, Trust large capacity rear diff cover, OS Giken rear LSD

Suspension/Brakes: SLR racing coilover kit, SLR adjustable upper arms, SLR GT knuckle adapters, SLR tension rods, SLR rear pillow ball camber arms, SLR rear pillow ball tension rods, SLR rear racing lower arms, SLR rear member brace, SLR front titanium strut brace, Nismo front lower arms, Endless monoblock 6-pot callipers/370mm rotors, Endless monoblock 4-pot callipers/332mm rotors, braided brake lines

Wheels/Tyres: Enkei RS055R 18×10.5-inch wheels, Toyo Proxes R888R tyres

Exterior: SLR GT full carbon body kit, C-West front bumper with added canards, SLR GT-spec carbon bonnet, SLR carbon boot lid, SLR carbon 3D GT wing, SLR rear LED light conversion, Craft Square carbon fibre mirrors

Interior: Bride Gias carbon seats, Nardi steering wheel, Nismo meters, SLR carbon door panels