Remember camping your butt in front of the tele to watch cartoons when you
were young? Well, if you’re now 25 years or older, chances are you can recall the
antics of Scooby-Do, Shaggy and the rest of ‘the gang’.
Wonder where they are now?
Well we’ll tell ya; they’re all over the bonnet of Mark ‘Mr Mechan-X’
Watson’s WRX! No, there wasn’t a messy traffic incident but these immortal
characters have been captured in the form of airbrushing.
When Mark – the owner of Brisbane’s Mr Mechanic-X workshop - decided he
wanted to explore the Scooby-Do theme for his Subie, he went to Craig from Head
Case Designs. Head Case Designs is responsible for some of the awesome
customised helmets worn by V8 Supercar drivers and drivers from overseas.
"It all started with a smaller Scooby airbushed on the boot," says Mark.
That was a cool subtle feature but then it was decided to give the car its
personality – the entire bonnet spent hours behind Craig’s airbrush. Top quality
House of Colour paint was used to airbrush the Scoob-ster, Shaggy and a haunted
house background. The result is an absolute work of art.
And rest assured there’s a whole lot more to this car than its comic theme -
it’s anything but comic under the bonnet!
Using a stock-internal EJ20 turbo engine, Mark has elevated his WRX to the
output of 225kW at all four wheels. This power comes from a locally fabricated
Noise Works 3 inch turbo-back exhaust, silicone intake hose kit, JR cylindrical
air filter, AVO blow-off valve, AVO oil catch can and a front-mount Option House
intercooler core with custom piping. Note that the big 3 inch plumbing into the
throttle meant relocating the battery to the boot.
Initially, Mark switched to IHI VF23 turbocharger which was spun to deliver
18 – 19 psi boost. This meant a high-flow fuel pump and a Xede interceptor was
necessary to deliver the appropriate fuelling.
Interestingly, the Nitrous Express nitrous bottle you see in the boot isn’t
used to feed the engine. Instead, it’s used to chill the front-mount intercooler
core using a dedicated spray bar. Mark tells us cooling the core with N20 is
worth about 15kW at the wheels on his car. The 10lb bottle lasts for about six
or seven full power hits and is triggered by a manual switch.
With up to 225kW at all fours (recorded on ChipTorque’s Dyno Dynamics chassis
dyno), Mark has had a great time toying with other ‘performance’ cars in his
area. Its straight-line credibility is established with an 11.9 second ET at 118
mph. Note, however, the 225kW ATW and 11.9 second performance came with the
fitment of a VF22 turbocharger. Mark has now reverted to a smaller VF23 turbo,
which gives improved response and reliability (Mark tells us he’s had two VF22s
"It’s good that I went through the problems that I did with the VF22," says
"I built the car as a test bed for set-ups that we apply to customer cars and
I’d rather find out about things like that on my own car."
With this level of performance – and a willingness to use it – the standard 5
speed gearbox proved far from reliable. After a couple of gearbox
disintegrations, Mark switched to an aftermarket dog box - but, still, he had
problems. He now uses a PPG dog ‘box, which has proven completely reliable.
Mark has also tested a number of clutches and discovered the best all-rounder
is a full-face organic clutch from Direct Clutch. We’re told an organic clutch
lining is much gentler on the flywheel than other materials.
The AWD Rex has no problems getting its power to the ground but its
factory-tuned chassis lacks finesse when you’re barrelling towards corners like
you can in this monster. Mark has fixed the situation using Whiteline heavy-duty
swaybars (complete with heavy-duty mounts and links), an anti-lift kit, front
strut brace, adjustable Koni dampers and Pedders lowered springs. The ride
height is about 2 ½ inches lower than stock and handling is described as
Gripping the tarmac are 215/45 17 Toyo Proxes stretched over jewel-like
Avantec R320 polished 17 inch alloys. Behind the spokes are DBA drilled and
slotted discs running Bendix Ultimate pads on the rear and MRT pads on the
Mark says the MRT pads made a tremendous improvement. "They give awesome
feel and don’t fade," he says.
Aside from its unique airbrush theme, the Impreza GC8 body is livened-up by a
C-West front bar and a STi driver’s side bonnet scoop (which replaces the
standard vent). Note that, on Mark’s car, the STi scoop is used feed air to the
filter. Other detail changes are clear taillights and side indicators.
The interior has swallowed an AutoMeter boost gauge, Sony head unit and
elaborate seat covers tailored to suit the Rex’s wrap-around pews.
So where to from here?
Well, since our photo shoot Mark has added a cryogenic-cooled intake system
and is in the process of building a bullet-proof EJ20 to handle a big hit of
With 10 second ETs in realistically sight, this is gonna be one fast
Mr Mechan-X +61 7 3205 1994
ChipTorque +61 7 5596 4204
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