NX Coupe Creation

In Australia, the Nissan NX coupe is completely overlooked as a car with performance potential. The NX has creditability almost line-ball with the Toyota Paseo – the ‘sportscar’ that was born without a pulse.

But few people put two an’ two together and realise that the NX is the perfect recipient for a SR20DET or, even better, a Pulsar GTi-R spec SR20DET. And that’s what we have here – a NX with a supercar engine!

Call it a NXi-R...

David Hallewell purchased this early ‘90s NX coupe a couple of years ago and, like most examples, it had survived without modification. It was stock all the way down to its 13 inch rims and non colour-coded bumpers.

But David had big plans from Day One.

Before anything happened under the bonnet, it was a priority to step up the appeal of the body and interior. The standard NX body was treated to the full colour coding treatment, the stock rims were replaced with 17 inch Avantec alloys and the ride height was brought down 1 ½ inches using off-the-shelf aftermarket springs. David didn’t want to add a body kit so he opted for some custom airbrushing. The NX bonnet now features an eagle sinking its claws into the Nissan emblem – a brilliant artwork performed by Steve from Daggerline Murals and Race Lines. There’s about AUD$1000 invested in the bonnet and, more recently, some matching vinyl graphics have been splashed down the sides. These are subtle rather than look-at-me.

Ahhh, and where do we start with that full custom interior? Well, the original front seats are replaced with Monza items and the rear seat has been removed to make space for a killer audio system and nitrous bottle. The floor is covered in checker plate and complementing silver paint is applied to various plastic trim pieces. Even the steering wheel, gear knob and billet window winders are in keeping with the colour scheme. The door trims are also custom trimmed with ‘Sir NX’ embroidery. Darren from Richardsons Trimming can be thanked for the majority of interior trimming.

David says the dashboard and whole interior was stripped from the car during installation of the audio visual system. And it’s one heck of a system. At the front you’ll find a Clarion Dolby surround sound CD tuner, a 7 inch LCD screen and a Sony Playstation 2 (which can be used to play DVDs and send audio signals through the Clarion Dolby system). The front speakers are Focal 6 ½ inch splits while the rear contains Kicker Impulse 4 inch two-ways and a pair of Rockford HE 12 inch subs.

Pop the rear hatch and you’ll see those big Rockford subs together with three Rockford amps – a 300X bridged to power the front splits, a 200S driving the rear fill speakers and a 400.4 (costing AUD$1600) to feed the subs. All of this is integrated into a neat custom built enclosure. The enclosure also comprises a hollow section that allows the NX’s removable roof panels to be stowed. Joel from Performance Car Audio can be thanked for much of the install.

Take a look around the cabin and you’ll find a host of gauges. There’s a trio of Speco gauges mounted flush in the passenger side of the dashboard (these gauges showing battery voltage, oil temperature and boost pressure) while a second boost gauge is mounted on the steering column. It’s easier to see there.

Now it’s time to lift the bonnet.

Gone is the factory 105kW SR20DE and in its place is a 169kW turbocharged version pulled from a Japanese market Pulsar GTi-R. David says the conversion was pretty straightforward as all necessary parts were stripped from a complete GTi-R half-cut. David gave Tim from TN Racing a hand during the conversion. David can be credited with the splashes of under-bonnet colour and mesh.

With the complete wiring loom and ECU available from the GTi-R half-cut, it made sense to swap everything into the NX coupe – this maintains OE reliability, keeps cost to a minimum and keeps the legal eagles happy. So the engine runs the standard GTi-R management system (which uses an airflow meter load input) along with the standard ignition system and injectors. A ‘500hp’ Walbro pump pushes fuel to the turbocharged donk.

The GTi-R engine has been tied to the original NX Coupe 5-speed gearbox and, although it’s not a perfect bolt-on, it has been performing without hassle. Redline gear oil and an Exedy heavy-duty clutch are the only alterations to the original driveline.

Interestingly, David chose not to fit an aftermarket intercooler and instead modified the original GTi-R core to fit in the nose of the NX. This required custom end-tank modification and mandrel bent plumbing. David says front mounting the core should improve cooling performance compared to the original top-mount position - and it also eliminates the need to cut a hole in the bonnet. Through that AUD$1000 mural...

The air intake flows nicely thanks to a 02 Rush pod filter and a GFB blow-off valve connected to the pipe between the intercooler and quad throttle bodies. Boost pressure from the standard T28 turbocharger is upped to around 16 psi using a GFB Atomic bleed valve.

Interestingly, David runs the GTi-R engine with the majority of the original NX coupe exhaust in place. The pipework is mainly 2 inch and there’s a straight-through muffler at the rear. We can only guess that the existing exhaust is keeping a lid on performance but, still, the car has spat out 213hp (159kW) at the wheels on 16 psi boost. The best quarter mile time to date is a 14.0 ET at 104 mph – but with only 12 psi boost.

"It’s magic to drive," says David.

"I mean, it’s not crazy stupid but it will give most cars a touch up," he says with a smile.

We bet it does!

At one stage, the engine was hooked up to a 55hp nitrous system but David says this made the car uncontrollable. It was too much grunt in one large hit for the front tyres to handle – so the system is now disconnected (with the tank remaining inside the cabin).

The current plan is to upgrade the exhaust – that oughtta give the NX all the power it could ever need. Aside from that, David might do a bit more bodywork and will continue to enter the car in shows – already, his NX has won plenty of gold.

And when you take a look at the creativity that shouldn’t come as a surprise.

Contact/Thanks Richardsons Trimming +61 7 3281 4239 David would also like to thank to everyone who helped with the car as well as his family, QuattroTech Racing club members and his wife Latisha.