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Mark Miocevich’s gut feeling to limit mods to his GT and concentrate on the detail was spot-onSource: Street Machine Magazine | Story: Craig Parker
Photos: Helmut Mueller

SOME cars are good from afar, but far from good. Mark Miocevich’s flawless black XB GT hardtop is stunning from a distance and gets better close up. It knocked everyone for six when it debuted at Summernats, slotting itself into the coveted Elite Top 10.Mark’s no stranger to Aussie muscle cars. Over the years he’s owned a variety of GTs, Monaros, SLR 5000s, Sandmans and SSs. He decided on a Falcon hardtop for his ultimate street machine for its wheel arches. He wanted to keep the car close to WA-legal, but with plenty of meat under the rear. With its generous wheel arches, sexy Coke-bottle styling, four-wheel disc brakes and healthy V8 up front, the big mid-70s coupe was perfect.

Bought in 1992, this was a $5000 roughie – a previous owner left her with a mangled bonnet, peeling paint, jammed sunroof and seven spluttering cylinders. But the under-floor areas and rear quarters were almost perfect. Mark searched for new and good stock, turning up a bunch of goodies including new doors (in FoMoCo boxes), new guards, bonnet, bumpers and even new tail lights – which a workshop visitor nicked, forcing Mark to opt for a set of XC repros.

Although he intended to build a showstopper, Mark felt that revered cars like his GT shouldn’t be messed with too much so he decided to minimise body mods. The bumper bar bolts were shaved and the battery recess from the driver’s side inner fender was filled along with all the unnecessary holes and seams in the engine bay. The underbody seams were stitch welded and the spot welds lovingly smoothed – a thorough tidy up rather than wholesale changes.

Having been a car dude for years Mark knew who was capable of show-winning work, hence his choice of painter. Over the past decade a swag of cars wearing Mark Thomlin on (B&B Smash, 08 9410 1806) paint have won best paint awards on the Perth scene, so commissioning him to lay on the factory Onyx Black (with silver accents) color was a no-brainer. The big coupe was put on a rotisserie so the underbody could be worked on as well and a year later it emerged with one of the most stunning bodies and black paint jobs you’re ever likely to come across.

Rather than use stickers for the GT 351 decals, they were reverse masked and sprayed on. About then the project ground to a halt. Mark swapped welders and spanners for a hammer and saw, devoting himself to house, not car, construction. Six years later the black shell was dusted off. Brothers Gary and Brad, and friends Ray and Wayne – who usually rocked up with slabs of ale – were a huge support throughout the project. Back in full swing, the crew worked over every nut and bolt.

Pop the bonnet and the EFI’s eight gleaming trumpets grab your attention. The trick set-up was a joint venture between Injection Perfection (02 9791 3122) and VEEM Engineering (08 9455 9355), which is co-owned by Mark and his brothers and was responsible for many custom pieces on the GT. Feeding Injection Perfection throttle bodies (on a Redline manifold, 02 9771 5877) is a pair of custom fuel rails all controlled by a MoTeC M48 Clubman ECU. Also controlled by the MoTeC ECU are four individual coil packs hidden in the polished plenum that runs between the gleaming trumpets. VEEM fabricated the combination hidden oil pump drive and crank-angle sensor.

Finishing off the immaculate engine bay is a tiny Corolla wiper motor hidden behind a flush cover and a snug-fitting firewall hole for the steering column. Re-manufactured brake and clutch lines run outside the engine bay, fuel lines run through the chassis rail and all the hose clamps in the engine bay have been replaced with aircraft-style screw fittings. Mark ground and smoothed the block before having it sprayed in an aluminium coating and polished by HPC Coatings (03 5662 4338).

K&D Chrome Metal Finishers (08 9493 4390) is responsible for the rest of the sensational polish and chrome plating. At a stroke-enhanced 377ci the mill is as strong in the grunt stakes as in the looks department. Crow Cams (03 9357 0469) supplied a complete combo including Crow hydraulic roller cam, full valve train and a pair of CHI alloy heads. West Racing (08 9446 1913) got it all purring like a kitten, and the combo turned the dyno to the tune of 530hp@6000rpm on PULP.

“That was very cool,” declares Mark. “I asked for a mid-500 combo and that’s exactly what I got.”

Sending the grunt south is a polished Richmond Gear six-speed manual and the obligatory nine-inch. It’s no ordinary nine-inch, though. All the brackets have been filled and smoothed (which took about 60 hours!) and it’s fitted with a Strange aluminium carrier and 3.00:1 LSD gears, while 31-spline Moser axles hang out either side. Joining the diff and ‘box is a VEEM chrome-plated 3.5in tail shaft featuring heavy-duty 1330-series Spicer units.

Exhaust Dynamics (08 9277 7400) bent a custom stainless steel system (with Pacemaker extractors) that’s a tubular work of art. Keeping things cool is a Maitland Performance Fabrications (08 9371 6786) triple-pass aluminium heat exchanger.

Increasing the whoa-factor are pizza-sized 343mm Harrop discs clamped by Harrop four-spot calipers, which almost stopped the car making Summernats. Colin Mac managed to source some missing brake parts only hours before it was due to be loaded into the container. The anchors completely fill the 17-inch Simmons F90s.

“God bless Chevrolet for making the ZR1 Corvette!” declares Mark, as its 315/35 ZR17 rear tyres fill the cavernous wheel arches perfectly.

Sumptuous leather inside is by Greg Malone. “Greg rescued me after the first leather trim set didn’t work, and did a great job finishing off the boot as well,” states Mark.

To give the GT’s nose a closer look at speed humps, WA Suspensions (08 9244 2211) slotted in one-inch shorter springs. GT rear leaf springs are standard height, but new nylon slippers between the leaves smooth the operation. Adjustable Koni shocks all round manage bounce, while roll control is the job of Whiteline (02 9603 0111) sway bars front and back.

With the project nearing completion and Mark between houses, the GT’s final preparations were completed in a rental. Imagine the landlord’s face if he’d walked into his garage and seen the GT up in the air on a hoist, with a block and tackle hanging from the rafters and a shiny Clevo swinging off it!

Mark has kept the car registered since he purchased it but recently added the FAT GT plates. As for staying legal, Mark promises: “Before I die I’ll build a car with a 6/71 huffier through the bonnet.” But for now he’s pretty chuffed with the response FAT GT has attracted. We asked Mark what he’s going to do with the car now. “Drive it like I stole it of course!”

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Fat GT Photo 1
Fat GT Photo 2


Color: Onyx Black with silver accents
Engine: Stroked 377ci Cleveland
Crank: Offset-ground 4MAB
Rods: Steel, 6in Chev H-beams
Slugs: Forged Ross
Cam: Crow hydraulic roller
Heads: CHI alloy high-port 4Vs
Rockers: Yella Terra roller rockers
Intake: Injection Perfection/Redline
Throttle Bodies: Injection Perfection
Computer: MoTeC M48 Clubman
Gearbox: Six-speed Richmond Gear
Diff: 3.00:1, LSD Alloy Strange 9in, Moser
31-spline axles
Springs: 1in lowered Lovells (f), Std GT
with nylon slippers (r)
Shocks: Adjustable Konis
Swaybars: Whiteline
Brakes: Harrop 343x31mm and 343x28mm
rotors, four-spot calipers
Seats: Nissan Skyline GTS
Wheel: Momo
Gauges: Factory GT
Rims: F90 Simmons 17×8.5 (f), 17×11 (r)
Rubber: 255/40 ZR17 (f), 315/35 ZR17 (r)

Below: When Mark says his discs completely fill the 17-in wheels he means it!

Fat GT Photo 3

LOOK MA NO BELTS! THE engine bay proved to be one of the project’s trickiest tasks. The initial idea was to drop an overhead-cam Ford Triton V10 between the Falcon’s stock shock towers – not a problem lengthwise, but absolutely no chance in the width department. Plan B – make the engine look like it has no moving parts. Yep, look closely and you’ll notice there are no drive accessories. A Davies Craig electric pump displaced the water pump, while a polished billet cover plate hides the harmonic balancer. But what about the charging system?

After considering and dismissing both tail shaft and hydraulically-driven alternator set-ups, they came up with the idea of driving a tiny Daihatsu unit off the back of the crankshaft. VEEM machined up a custom pulley/flywheel spacer so that the drive belt comes out between the back of the engine block and the flywheel on the opposite side to the starter motor – luckily the gearbox input shaft had sufficient length to allow the ‘box and Dellow Automotive (02 9774 4419) bell housing to be spaced back by 15mm. And it was also good fortune that there were existing bolt holes to mount up the alternator in this unusual location. The set-up has run hard on the engine and chassis dyno with zero problems – nifty eh

Fat GT Photo 4
Fat GT Photo 5
Fat GT Photo 6