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This article was first published in 2002.
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Feast your eyes on one of the most magnificent cars AutoSpeed has ever presented. Yes, yes, we know it's a little 'buzz box' Daihatsu Mira, but underneath that relatively standard looking body is pure racecar engineering. While a racing Mira can be taken only so seriously, the hardware of this little beauty is deadly serious - try carbon fibre panels, a full roll-cage, fabricated racecar suspension, massively upgraded brakes, four-wheel-drive, launch and traction control and a power-to-weight ratio of nearly 300hp (224kW) per tonne!
The man behind all this madness is Adelaide's Ian Richards. Ian's no fool when it comes to building racecars or driving fast - he's built Formula Libra, Formula 3, Formula 2 and Formula Holden open-top racers and competed in just about every form of circuit motorsport (including Bathurst in 1972). So what the hell made this guy dedicate four years part-time to hot-rodding a Mira? Simple - he's an extrovert!
The basis for this project was an early '90s Daihatsu Mira X4, which Ian imported from Japan. The X4 is one of the 'gun' Kei class cars, if you could say such a thing. In standard form it comes powered by a 660cc 3-cylinder, 12-valve engine with EFI and a tiny intercooled turbo. The official quoted 48kW (64hp) is channelled through a constant all-wheel-drive system, meaning the X4 is something of a miniature rally weapon.
After taking delivery of the car, Ian pretty well immediately got stuck into a full rebuild - and we mean full rebuild...
The theme for the car was minimum weight, a near-standard appearance and a relative abundance of power. That last concept prompted Ian to discard the standard 660cc turbo engine for the 993cc 'big block' twin-cam turbo out of the Japanese Charade GT-ti. Ian tells us the conversion was pretty tight, necessitating solid mounting the engine about 40mm lower and 40mm rearward of the standard engine location. This meant also having to modify one hole on the gearbox housing. A meatier radiator - from a Nissan Exa - is installed, along with an electric fan. The intake and exhaust manifolding was to be fabricated, so clearance of the standard manifolds was not an issue.
So what the hell do you do - or what can you do - to tweak a 993cc turbo?
Ian left the GT-ti engine's internals standard with the exception of a modified sump, a slight head tidy and a pair of Wade camshafts. These were dialled into their optimum position using custom sprockets while the engine was being tuned on the dyno. On the intake side, the lower half of the standard manifold remains bolted to the head, but the top section is fully fabricated. Ian whipped up a trio of 40mm throttles (complete with bell-mouth inlets) feeding from a shared plenum chamber. A UK-sourced blow-off valve is incorporated in one end of the plenum. Oh, and - while we're talking intake - check out the carbon fibre induction tube leading into the compressor inlet; the opposite end draws air through a foam filter inside the ventilation chamber at the base of the windscreen.
The manifold is pressurised up to 1.6 Bar thanks to an extensively modified T2 turbocharger blowing through an Ian-fabricated front-mount air-to-air intercooler. Exhaust gasses are fed into the turbine via a custom fabricated tubular manifold. The remainder of the exhaust is a 2 ½-inch pipe leading into a 3-inch with a F3 Inconnel muffler (!).
Ian spared no expense with the engine management, opting for a MoTeC M4E Pro with an in-built MAP sensor. The MoTeC fires a set of three ex-Nissan FJ20 Turbo injectors, feeding from a GT-ti rail with the standard GT-ti regulator. There's no external swirl pot, but the Bosch fuel pump is ensured a constant supply thanks to the existing in-tank baffle system. Ignition comprises a single Bosch coil, Eagle 8.8mm leads and '9' heat range NGK spark plugs. The rev limit is set at 7200 rpm and there are two separate sets of maps for Synergy 8000 98RON pump fuel and Elf LMS race fuel. The MoTeC is also set up to deliver launch and traction control, but - at the time of writing - neither had yet been tested. In any case, there's plenty of grip on offer from the slick racing tyres.
Bolted to the engine dyno of Bill Hanson Engine Developments, the little slugger punched out a maximum 180.1hp (134kW) and 169.7lb-ft (231Nm) on 1.4 Bar boost and with Elf fuel squirting through the injectors. Ian says 200hp (149kW) would be easy with a bit more boost and camshaft lift. As it is, though, he likes the fact that it's a torque monster - there's a mountain of grunt waiting after every gear change.
And would the stockie X4 driveline be able to handle this much duress? Not likely, so Ian fitted an AP twin-plate clutch and called upon Fitzner Engineering to produce a straight-cut dog gearset. The front axes are built around the relatively beefy Daihatsu Applause CVs, with custom shafts. A custom short-shifter arrangement inside the cabin enables speedier changes as well as locates the shifter a little closer to the driver.
While all the engine and driveline was taking shape, the body had been completely stripped. Ian got stuck into the Mira's insides, decking it out with a proper CAMS-spec chrome-moly roll cage. This extends from the rear suspension towers through to the firewall and - in a separate section - through to the nosecone. Ian tells us the cage adds 37 kilos and - in addition to providing increased safety - makes the chassis dead stiff. The perfect basis to hang a top-grade suspension arrangement...
Ian's racecar experience is evident in the suspension - check out the front suspension, which uses 'A' wishbones with NMB rod ends along with a custom 'overhead' 3-point adjustable anti-roll bar. Under the live axle rear there's trailing arms and a Panhard rod with an adjustable (conventional style) anti-roll bar. Custom springs were wound to Ian's specs, while damping is left to Konis at the front and SPAXs at the rear.
At the time of our photo shoot Ian was in the process of upgrading the braking department. He'd originally set out with a Girling master cylinder, standard GT-ti discs and calipers at the front and Applause rear rotors and GT-ti calipers at the rear. After a bit of track testing, however, Ian wasn't happy with the pedal pressure, so he's now moving to an even bigger set of '94 Toyota MR2 discs and Series 4 Mazda RX-7 calipers on the front.
Despite the fitment off all this good gear, Ian's gone to extreme lengths to ensure the car is no heavier than standard...
One of the most impressive aspects of the vehicle its carbon fibre panels - the bonnet, front guards, bumper and tailgate were carefully custom moulded by Ian. Taking the 'wet lay vacuum bag' approach, Ian says the carbon fibre was a painful exercise involving making at least two of every panel to get it right. The remnants of the first attempts still lay around his workshop.
Interestingly, Ian's kept record of component weights; the carbon front guards weigh 1.2kg in total (saving 2.4kg), the carbon fibre/Perspex hatch weighs 6.7kg (saving 13.3kg), the doors now weigh a total 20kg being gutted and fitted with Perspex windows (saving 22 kg) and the Perspex rear quarter windows tip the scales to 3.6kg (saving 2.8 kg).
Other dieting measures include removing the hood lining, the rear seat and belts, carpet and replacing the door trims. Ripping out the sound proofing shed 13.5kg, stripping the dashboard (including the column and fitting a lightweight steering wheel) saved 5.2kg, removing surplus steel brackets saved 1.8kg and - get this - Ian thought the factory valve cover was a little on the portly side, so fabricated an aluminium replacement!
Interior items that Ian's deemed important enough to add include lightweight Momo seats, a Willans harness, SPA suede steering wheel, fire extinguisher, a Tilton adjustable brake bias handle and gauges for gearbox, oil and water temperature, plus boost, oil and fuel pressure. Oh, and don't overlook the ArmTech sequential shift light and flat changer.
So how heavy did this 180-ofdd horsepower AWD monster end up? A mere 618kg (without fluids), or - to put things into perspective - around half the weight of a GC8-series Subie WRX! Need we say any more?!
After its maiden track debut, Ian says the car performed exceptionally well - and that's high praise, coz not many built-from-scratch vehicles make a problem-free first appearance. As mentioned earlier, though, he found the brake pedal pressure a bit too firm, but - other than that - everything's well on-track. It handles nice and tight, it's stable and, of course, shatteringly quick. With four years of toil behind him, Ian's now ready-and-raring to get in there and start shaking up some of the high-profile tarmac motorsport events; bring it on we say!
Oh, the embarrassment of being wasted by a 3-pot Mira!
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