The R33 Nissan Skyline GTS25T is presently one of the most popular Japanese imports in Australia - and Matt Lowth's burgundy M-spec 5-speeder is a good example of why...
Like many R33 GTS25Ts, Matt picked this particular unit up with a fair load of aftermarket go-fast goodies already fitted. The previous owner had spent up on a 4-inch thick Blitz front-mount air-to-air intercooler, an A'PEXi Power air intake, GReddy Type R blow-off valve and a Trust 3½-inch sewer system. An adjustable boost system was found under the bonnet but - oddly enough - wasn't hooked up. It seems likely that it had been connected at some stage, however, because the standard injectors had been ditched for a set of bigger 550cc jobs and the management had been altered with a Tomei chip.
Externally, the Type M-body kit - which includes side skirts, a rear apron and revised front bar - had been treated to an aftermarket towering rear wing. No one's sure who the manufacturer is, but the proportions are very similar that of a Nizmo product. Obviously, the conservative Nissan alloys had also been removed in Japan and a set of 5-spoke 17-inchers was slipped on. These look aggressive without having that fussy style that's all-too-common in Japan. It also appears that - in search of traction through the Nissan IRS - a Cusco mechanical diff has been included in the deal.
In summary, Matt's R33 arrived as a good example of what 'the lads' build in Japan.
Having moved up from a very humble conveyance - a Holden Camira - Matt was blown away by the Skyline's performance. As always, though, there were a few areas where he could sharpen things up. The most annoying aspect of the car was its cough-coughing under bulk-rich air/fuel mixtures. Strangely enough, the engine management side of things rarely seems to be done 'right' by the Japanese enthusiast. So, in order to send a different load signal to the Tomei-chipped ECU, Matt went out and installed an A'PEXi AFC. With a bit of fiddling around, the AFC provided much smoother running - it wasn't perfect, but it was a hell of a lot better than before.
Happy to drive the sweeter-running R33 as-was, Matt squeezed in a couple of other mods as time permitted. Number One was installing a flexible cold air induction pipe (seen swallowing from a pick-up in the left side of the bumper), followed by some heat tape wound around the intercooler pipes. That kept intake air temperatures a bit cooler - an important consideration when you're running Australia's up-to 98-octane fuels. Also reducing the chance of detonation is a blow-by oil catch can - you don't want oil sludging up inside the intercooler or passing into the combustion chambers.
Next came a little bit of work on the brakes. Matt had the standard discs grooved and a set of Bendix Ultimates installed for more braking power and consistent performance.
Oh, and about the same time, the comfy Type M interior was treated to an A'PEXi mechanical boost gauge and a new audio system. Pumping sounds is a Nakamichi MB75 6-stack head unit teamed with Focal 6½-inch front splits and Orion Cobalt 6-inch 2-ways on the rear shelf - Matt tells us the last thing wanted was a heavy stereo system. The only other non-standard item indoors are the Japanese-fitted Razo pedals and gear knob.
With things humming along pretty smoothly, Matt kept looking toward that engine management concoction of an aftermarket chip and the AFC. Sure, he could adjust fuelling in a few stages, but what the heck was the ignition timing set at?
Good question.
Wary of now running up to 14-psi boost, Matt ripped out the AFC and had a Unichip wired in. Again, this was a step in the right direction, but Matt says the car never really ran to its potential. With a second-hand replacement turbo now bolted on (ex Nissan VG30DET), "only" 185kW was seen at the back wheels (on 14 psi). It was goodbye to one barely used Unichip.
The third - and final - management change was the fitment of an A'PEXi Power FC. It seems you can always depend on a Power FC to give good quality starts, idle, response and all the smooth-running niceties that you should have in an everyday vehicle.
The Power FC also has a tricky little function that lets you plug in a larger, higher-flowing Nissan airflow meter (out of a Z32 300ZX) and maintain the correct fuel and timing. So, with the Power FC and a 300ZX airflow meter in place, Matt's car now pushed out 183kW at the rears using only 11 psi - just 2kW down on the previous run using 14 psi and a Unichip.
With sizeable torque loads passing through it, the standard clutch started slipping - badly. Without going too ballistic, Matt solved this problem with an Exedy-Daikin heavy-duty clutch and a 2200lb pressure plate. Now there's no slip - or leg quiver.
It's just as well the clutch upgrade came when it did, coz a bigger turbo was quickly required. It seems the (second-hand) VG30DET turbo was a bit stuffed. So, rather than go for another ceramic turbo lucky dip, Matt opted for a conventional high-flow turbo built using metal wheels. The new turbocharger uses a T04E front cover and a Mazda RX-7 rear, using a ported wastegate.
With 14 pounds of boost, the R33's RB25DET engine is now generating a sunny 206kW at the wheels. Getting up there for a stock-internals 2.5-litre!
With 206,000 Watts at the back wheels, the rear-drive R33 chassis was beginning to feel noticeably over-powered. Lucky there's a heap of aftermarket suspension gear to suit - Matt installed Bilstein shocks, Whiteline 25mm lowered springs, adjustable front and rear swaybars, castor and rear camber bushes.
Out on the road in its current guise, Matt's car is a real blast. It hauls hard in a straight line, and - when he sticks his boot in mid-corner - you can be assured of some drift action! Power slides - despite the 255/40 Azenis rear rubber - are just a thought away.
And what thoughts does Matt hold for the future?
Well, you'd think he'd be content - but, damn it, there's some truly fast cars out on the road these days. So, to be sure of maintaining that competitive edge, Matt is planning on going for a RB30 bottom-end, T66 turbo and running around 300-plus rear wheel kilowatts.
TRYMEI - but only if you think you can keep up!
