Let’s get one thing straight about fast Kei cars, the only thing diminutive about them is their size. That’s pretty much the only thing kei about them, everything else is more or less the same as compared to their more orthodox sized brethren.
You might be fooled into thinking that your dollar could be stretched more but unless Monopoly money becomes legal tender, you’re blown out of luck. These tiny terrors cost some serious coin to get done up and is quite the acquired taste, so it isn’t exactly for every Tom, Dick and Harry.
The turboed Myvi gracing these pages was built to pay homage to the iconic D-Sport Boon X4. It’s probably common knowledge for the kei car enthusiast but Daihatsu actually developed a turbocharged, all-wheel drive version of the Boon, labeled the X4. Although that model came with a turbocharged one-liter engine to conform to kei car rally regulations the, D-Sport replica here packs the 1.3-liter mill under the hood and makes do without the all-wheel drive.
Starting with a K3-VET engine, the entire thing was stripped out for a complete rebuild to cope with the larger snail and uprated boost. All the internals were fully-balanced for heavy duty under high revolutions. The head, throttle body and intake manifold weres binned in favour of the equivalents from a 3SZ-FE, the larger 1.5-liter lump you would find under the hood of the Alza locally and other Daihatsu models.
A custom extractor was designed specifically for the engine and was ceramic-coated to endure higher temperatures. It connects to a complete D-Sport 2.5-inch exhaust system constructed from high-grade steel piping. Fueling is handled by injectors from a Mitsubishi GSR engine that are fed by a Walbro in-tank pump with a Sard fuel regulator keeping the pressure constant during spirited drives.
The stock turbine was replaced with a larger AR80 Garrett unit, capable of higher boost levels and producing more power. A Tial 38mm wastegate and HKS SSQV blow-off valve handle all boost related pressure governing while a custom intercooler keeps ambient temps down before entering the combustion chamber. Engine cooling is taken care of by an aluminium radiator and a radiator fan nicked from an Evo 8.
Finally, a handful of miscellaneous mods do their bit to keep the engine running as optimally as possible. On that list would be the Hot Inazma Voltage Stabilizer, Samco silicone hoses, GReddy oil catch tank, GReddy oil cooler, D-Sport engine oil cap as well as a D-Sport radiator cap.
Although the engines are pretty small dimensionally, it takes some big computing power to keep them pushing out big numbers. With that, GReddy came to the rescue with their E-Manage Ultimate and electronic boost controller. A number of Defi gauges in the cockpit help the driver keep an eye on the engine’s parameters such as boost levels, water temperature, oil temperature and oil pressure.
If engine water temps start heading north, the driver can switch on the fan manually with the Pivot fan controller. You’ll also find an ARK turbo timer in there to help the engine settle down before shutting off.
Although the K3-VET came with a tiptronic transmission, for this application, a five-speed manual was maintained to allow for spirited driving. Nonetheless, an LSD was fitted up front and custom gear ratios were machined for optimum acceleration. Limiting slip during hard launches is a D-Sport super single clutch set.
D-Sport once again came to the rescue in the ride and handling department. A full set of their high-performance B-Spec suspension were fitted in the four corners to reduce body-roll and keep the tyres planted to the asphalt as much as possible.
Suitably, the brakes had to be beefed up as well to better reign in all that newfound motivation. The rotors and calipers from an EK9 Honda Civic were refurbished and fitted to the Myvi, giving it disc brakes at the rear as well for peace of mind. Hiding those gold calipers and filling the arches are a set of bronze Wedssport SA90 wheels measuring 15×7-inches and wrapped in ultra-sticky Yokohama Advan Neova AD08 rubbers. A set of D-Sport lug nuts do well to compliment gold brake calipers and hold the wheels in place.
A major part of transforming the car into a D-Sport Boon X4 replica comes from the exterior pieces. For this, the owner decided there’s nothing quite like the real deal and got his hands on a set of complete, bonafide D-Sport Boon X4 body parts, making this quite a special and unique little hatch indeed. Completing the exterior transformation is a carbon fiber scooped hood, carbon fiber rear spoiler and adjustable smoked HID headlamps of a JDM Boon.
All that beauty would only be skin deep if the Boon transformation didn’t extend all the way to the inside. A genuine Boon X4 dashboard is joined by the door trim and gear console to complete the mirror image.
The driver steers with a Momo tiptronic steering wheel while seated snuggly in a Recaro Tomcat D-Sport Kevlar semi-bucket seat and held in place with Takata four-point safety harnesses. D-Sport provided the gear knob and floor mats with Tiffana House coming onboard to lend the rear-view mirror.
In-car entertainment is handled by a Kenwood head unit feeding through to a subwoofer and satellite speaker from the brand as well. Caliber rounds up the simple sound system with their four-channel amplifier mounted together with the subwoofer in the boot.
What this miniscule Myvi lacks in size, it certainly makes up for with quality components, a fistful of power under the hood and more JDM-ness than you could have possibly imagined. It’s kei cars such as these that give the category its undeniable appeal and instills respect for them from all petrolheads.
Car: Perodua Myvi 1.3 EZi 2005
Engine: Daihatsu K3-VET, fully-balanced internals, custom ceramic-coated extractor, GSR turbo injectors, head + throttle body + manifold from 3SZ-FE, AR80 Garret turbine, custom intercooler, HKS air filter, HKS SSQV blow off valve, Hot Inazma Hyper Voltage Stabilizer, Tial 38mm wastegate, Samco silicone hoses, aluminium radiator, Walbro fuel pump, Sard fuel regulator, Evo 8 radiator fan, GReddy oil catch tank, GReddy oil cooler, D-Sport complete 2.5-inch exhaust system with steel piping, D-Sport engine oil cap, D-Sport radiator cap, relocated battery to the boot
Electronics: GReddy E-Manage Ultimate, GReddy boost controller, Apexi RSM, Defi boost, water temperature, oil pressure & oil temperature gauge, Pivot fan controller, ARK turbo timer
Transmission: Five-speed manual transmission with LSD, custom gear ratios, D-Sport super single clutch
Chassis & Handling: D-Sport B-Spec suspension
Brakes: Civic EK9 front & rear disc brakes
Wheels: Rim Wedssport SA90 15×7”, Yokohama Advan Neova AD08 195/55/15, D-Sport wheel lugs
Exterior: Complete Daihatsu Boon X4 D-Sport body parts, carbon fiber hood, carbon fiber rear spoiler, smoked HID adjustable headlamps, Boon X4 dashboard + door trim + gear console
Interior: Momo tiptronic steering, Recaro Tomcat D-Sport Kevlar seats, Takata four-point safety harness, D-Sport gear knob, D-Sport floor mats, Tiffana House rear-view mirror, Kenwood head unit, Kenwood subwoofer, Kenwood Alien satellite speaker, Caliber four-channel amplifier
Garage: XTuned Motorsport (03-8733 3955 / 012-2133 577), www.facebook.com/xtunedmotorsport