Mr GTi

Step back to a time when a hot off-the-shelf Holden Commodore made around 180kW and one of the quickest hot hatches on the market was Suzuki’s Swift GTi. Through this early/mid ‘90s period, the little 1.3 litre DOHC hatch was the cult hot hatch.

But, despite its hot hatch label, the Swift GTi is not the sort of vehicle that immediately impresses in terms of raw performance. With 74kW/113Nm and a kerb weight of around 800kg, it’s a car that comes together when you’ve got the engine buzzing near its redline, threading up a mountain pass. Line up at a set of traffic lights and you’d best not be a betting kinda person...

But John Paul Costanzo’s ’97 Swift GTi packs a whole lot more performance than a stocker. A whole lot more...

About four years ago JP started looking at ways to get his hot hatch really sizzling. The easiest and most cost-effective approach was to lay down the cash for an AVO (Advanced Vehicle Operations) bolt-on turbo kit.

An AVO Stage 1 kit (fitted by Brisbane’s Motson’s Turbo and Suspension) gives the Swift a cast exhaust manifold, ball-bearing turbo, extra injector with Link micro-fueller, front-mount air-to-air intercooler and all necessary lines and fittings. A custom 2¼ inch mandrel exhaust was also fitted at this time. On 9 psi boost, this set-up made 118hp (87kW) at the wheels of JP’s Swift.

Unfortunately, a bad batch of fuel led to a major detonation event and the demise of one standard head gasket. The solution was the fitment of a more durable triple-layer steel gasket and, subsequently, boost was bumped up to 11 psi.

But that was all too much for the stock internals - cylinder number 2’s ring land went bye-bye.

At this point, the vehicle was again handed over to Motson’s for an engine rebuild featuring 8.5:1 static compression forged pistons and a 3-angle valve job on the cylinder head. The standard cams remain except with adjustable gears. JP’s brother, Rob, fabricated a 2½ inch 316-grade stainless steel exhaust running a TRP muffler.

With greater boost on the agenda, the Suzuki fuel system now runs a Malpassi rising rate pressure regulator and four Nissan R32 Skyline GT-R injectors controlled by a Link programmable management system. The previous micro-fueller arrangement was given away.

The now-gone airflow meter is replaced by a Motson’s fabricated flared adaptor pipe which connects the K&N pod filter. A stainless steel heat shield prevents under-bonnet air making its way into the engine. Motson’s also whacked in a custom oil catch can for good measure.

TurboSmart is the brand label on the blow-off valve and boost valve, while a Do-It-Yourself type intercooler water spray system (triggered by a Hobbs pressure switch) helps chill the intake air. The intercooler pipe that runs to the engine has also been wrapped in insulation in the vicinity of the exhaust manifold.

With boost pressure now safely cranked up to 14.5 psi, the next weak link in the Suzuki armoury was the driveline. After destroying one gearbox, JP installed an expensive (AUD$9000!) Suzuki Motorsport Group A gearbox containing helical gears, billet shafts and a very short 4.96:1 LSD. The clutch presently in service is a Motson’s unit providing a substantial 2400lb clamping force.

With the shortened final drive ratio (which is said to reduce measured power), JP’s GTi has recently blasted out an amazing 178hp (131kW) at the wheels on 14.5 psi. That’s one helluva lotta power for a little 1.3 litre engine with standard cams and a modest size turbocharger!

The new LSD apparently tugs at the steering wheel when accelerating hard from low speed but the car now grips and goes. JP hasn’t yet taken the car to the drags but all indications are that a 13 second pass should be quite easy – depending on how the altered gearing affects 400m performance.

Harnessing this speed is the standard braking arrangement enhanced with DBA slotted and drilled front discs and DBA slotted rear discs. Endless pads are also installed.

The GTi-spec suspension is tightened-up with Koni dampers, King springs and beefy Whiteline swaybars. JP’s brother also fabricated front and rear strut braces.

And check out the wheel arches – you won’t have seen 16 x 6.5 inch ROH Chicanes on a GTi before because these puppies are a one-off. Tyres are nitrogen-filled Federal 205/40 16s.

Open the door and you’ll find a small cabin packed with a very large sound system. JP runs a current Clarion head unit, PPI 4 x 100W RMS amplifier, Canton front splits and a dirty big pair of Orion 12 inch subs that consume the rear cargo area. An Odyssey battery and high-quality cables ensure the system operates to its full potential. JP says the system is set up to provide excellent sound across a variety of music styles – but that doesn’t stop it pounding out up to 146dB...

Also found inside is a Momo steering wheel, gear knob and pedals, an AutoMeter boost gauge and ‘MR GTI’ front seat covers.

So what plans does Mr GTi have left in store?

Well, now that he’s got that tough gearbox there’s no reason to hold back on power. An AVO ‘280hp’ ball-bearing turbocharger should give the 1.3 even more top-end whack and we’re told the suspension will probably be revised for something more accommodating of B-grade roads.

And did we menton JP’s brother has recently got in on the Swift turbo act? You’ll have to wait and see how the other Costanzo lad tackles the same theme...

Contact/Thanks:

Motson’s Turbo and Suspension                         +617 3277 7766
                                                                                     http://www.motsons.com.au/

JP would also like to thank his brother, Rob, for his help building the car. Thanks bro!