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Meaning Business: Function Meets Form in a Subaru Impreza STI

Pao Martinez' STI

Over the years, there has been a long-standing debate within the aftermarket world; to build a car purely for aesthetics and flair, or to build a car to be better at what it’s intended to do. The argument on form vs. function is probably one that will never end, as plenty of people will always have just as many opinions about one against the other. Yet in the midst of it all, the best builds out there are the ones that make both those opposing ideals meet.

Pao Martinez' STI rear

While obviously inclined towards clocking a fast lap, this GDB Impreza STI brings with it a menacing stance to turn heads as well. Built with choice parts that have as much function as there is form, rest assured that this STI is as fast as it looks. For starters, the front comprises of a CF Front Splitter as well as a pair of canards on each side to give extra downforce at track speeds. One thing that denotes that the splitter isn’t for show are the pair of APR Splitter Support Rods that keep it from falling off due to the air pushing down on the splitter at speed. Where you’d normally find fog lamps on a stock GDB, instead here you will find ducts that route to the brakes for added cooling, and not to mention that big intercooler up front. More on that detail later though.


Common sense dictates that a bigger footprint equals better grip. Whether for people or for cars, this rule of thumb is something to go by especially when the pursuit for speed is concerned. This STI makes full use of the sheer mechanical grip its 4WD powertrain offers by having a good chunk of rubber underneath those widened fenders. Shod in 265/35/18 Nitto NT05s all around, these 18×10 Rota RT-5s are wide enough to merit a pair of wide fenders in front and fender flares at the rear. Peeking underneath the thin spokes of the RT-5 is an AP Racing 4-pot Brake system for the fronts, a much needed upgrade given the amount of time this car gets taken to track!

Voltex wing

If you’ve acquainted yourself with the aftermarket world, you’d know that people would always have divided opinions on whether or not to install spoilers. While GT Wings mainly existed on racecars to provide downforce for more grip at high speeds, for the streets they’re mostly built for props and hardly have any function at road speeds. If this spoiler’s brand is any indication however, certainly this GT wing isn’t one of the latter. Voltex Japan has an extensive background in time attack and circuit racing, hence a lot of R&D have gone into their products to ensure that they will produce faster laps instead of mere ballast.


All that work on the exterior has to hold the grunt this motor gives as it guns around the track. Unlike the 2.5L EJ25s that our local STIs get, this GDB gets the JDM EJ20 2.0L motor with a factory twin scroll turbo. One of the main advantages of this motor is the higher RPM it’s capable of revving to, (8,000rpm vs 6,500rpm on the 2.5L) allowing for a better powerband around tight sections of our local circuits. That said a host of modifications have been implemented as well to make the most out of this setup. Prominent among these is hinted by the layout of hardpipes in the engine bay. That’s right, this Impreza’s motor is home to a Greddy Front Mount Intercooler kit that relocates the standard top mount intercooler of the STI underneath the front bumper. This allows the use of a larger intercooler core and keeps it away from heat sources like the turbo to avoid heat soak, albeit at the cost of a little turbo lag from the extended piping.


Provided this is a car that sees the track more often than most, its interior also has choice parts to keep the driver in check during a run. Upon opening the doors the first thing that stands out is the white Safety 21 6-point Roll Cage that contours to the dash and the rest of the cabin while providing added rigidity and safety for the driver in the unlikely case of an accident. To hold the driver and passenger in place, a pair of Bride Zeta 3’s have been employed as well. In building a car for the circuit, one of the key things to improve on are the input devices or anything that the driver himself interacts with. The rather rare Key’s Racing Steering Wheel has a simple and no-frills design that allows for the driver to easily interpret any bumps, changes in alignment, or changes in the car’s behavior in general through holding the wheel.

pao sti 2-2

A car built for function can always have form follow suit, and vice versa. In some respect, building a car just for one and not the other would seem like an excuse to not make a build perfect. The best builds out there showcase the right balance of function and form, and these builds make it seem that the argument between the two sides shouldn’t even exist to begin with. Perfection is the key to any build. Be it for aesthetics or for speed, know that a properly built car will take time, patience, and a rather large investment to pull off. And just like this STI, it will be all worth the trouble once you’re done and enjoying it.

2003 Subaru Impreza WRX STI

JDM 2.0L w/ OEM twin scroll turbo 8k redline
300whp/309wtq dyno tuned by pacho of autoplus
HKS intake
HKS downpipe
HKS Hi Power Exhaust
Grimmspeed Boost Control Solenoid
Silicon turbo inlet hose
Greddy BOV
Carbing Oil Catch Can
Greddy Front Mount intercooler
Mishimoto Radiator and fans
Silicon radiator hoses

Exedy clutch
Wantwin lightened flywheel

Tein Super Street Coilovers
Cusco front and rear swaybars
JC Racing Endlinks

18×10 Rota RT5
265/35/18 Nitto NT05 Tires

AP Racing 4 pot front brakes
Endless Rear Brake Pads
Goodridge Stainless Steel Braided Brake Lines

Bride zeta 3 seats with orig bride railings
Safety 21 6-point roll cage
Keys Racing Steering Wheel
Titanium Shift Knob
Pioneer Stereo
USDM panel gauge
JDM STI red hazard button

Voltex Wing
CF front wind splitter
APR splitter support rods
CF front bumper canards
CF OEM chin
CF Trunk(color matched)
Fiber Glass front wide fenders
Seibon reverse hood scoop
GT side mirrors
Brake duct provision on fog lamp covers
STI side skirt strakes
05-07 STI rear fender flares
05-07 STI rear bumper

Photos by Jet Rabe

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