15-02-2009 06:14 PM
Daihatsu Storia X4 (713cc VF36 Turbo'd 4x4)
Here's a little bit about my Storia X4. As they're quite rare, I thought I'd give a bit of history about the car first, and then detail the actual car how she stands:
History & Specifications
The Storia X4 was developed by Daihatsu as a base model for domestic use in motorsport events. Accordingly, luxury items such as air-conditioning, electric windows etc were removed to keep the weight of the car to minimal levels (although power steering was a cost option). Production began on April 10th 1998, and ceased on 31st January 2004. In this time, only 829 cars were produced. Daihatsu did not produce the cars through normal production for sale, and all cars were special order only, and were only available in white.
The base car started with a derivative of the 660cc JB-DET engine, and is a 4-cylinder Twin-Cam DOHC DVVT Fuel-Injected Intercooled Turbo-Charged engine. These engines were shipped to DRS (Daihatsu Racing Services - Think of them as TRD), where the cylinder capacity was enlarged to 713cc, and forged internals added. The 713cc engine size was specifically engineered to enable the car to race in the 1.0 litre class, whereby turbo-charged cars engine size are given a mandatory multiple of x1.4 (to ensure a level playing field against n/a cars). Given the cylinder size of 713cc, a x1.4 multiple means that the cars effective engine size is 998.2cc, thereby being as close to the 1.0 litre limit as possible.
The 713cc engine runs an IHI RHF4B VF36 Ball Bearing Turbo with a Titanium Shaft and Turbine Wheel. Intercooler water spray is also fitted to help lower intake temperature. Rumour is that the engines were slightly de-tuned for sale by Daihatsu, and left the showroom running 18psi (1.24bar), producing 120ps. However, an adjustable actuator was fitted as standard, allowing the boost to be increased to around 24psi with no additional modifications required. A performance upgrade was also available directly from Daihatsu when ordering, which apparently produced 200ps!
The car has a 5-speed close ratio gearbox, clutch-type front & rear differential and permanent four-wheel drive. The overall weight of the car is approximately 820kgs, so the car has an effective power-to-weight ratio of 146ps per tonne.
Unsurprisingly, when the car was introduced in the Kei-Jidousha class (Japanese Mini Cars), it decimated the competition thanks to it's light weight, power and handling. The car also enjoyed success in the all Japan Rally Championship and the all Japan Dirt Trial Championship.
I first came across the Storia X4 via Gran Turismo. At that time, I knew there was no chance whatsoever of getting my hands on one, as ESVA tests were enforced, and the limited number of cars available meant that a Model Report would never be created (unless of course, I shelled out for one myself).
Little did I know, that Daihatsu UK officially imported 3 of these cars to the UK with the intention of rallying them. For some reason, they were never rallied, and found their way into the hands of the UK public.
After the usual internet session, I came across one of these 3 cars for sale, and instantly started negotiations. I flew up to the North to collect it about a month later, drove it back, and dry-stored it for a year. This gave me the opportunity to start 'acquiring' parts for it. The car originally looked like this, complete with standard 165/65/14 alloy wheels, and an aftermarket DRS Mk1 front bumper and skirts:
The car had apparently been ill-looked after, and the previous owner set about 'rescuing' it with a full respray, and a new turbo (the original one had apparently seized) amongst other things. Unfortunately, this meant that the OEM adjustable actuator was no longer present. The previous owner spent a lot of money on the car, but finally decided to give in after getting it road ready (and after getting grief from the wife).
After a year of accumulating parts, it was time to start getting organised... The first thing to be changed were the standard alloys, where I discovered a nice set of D-Sport (think of D-Sport as TOM's) grooved discs and pads up front that had virtually no wear at all. An MOT was then acquired (passed 1st time with NO advisories), and as steveep82 owed me a few favours, the car was given to him to take on the challenge of fitting the parts to the car, and to fabricate a turbo-back exhaust system. After about 4-5 weeks, the parts had all been fitted to the car, and the current spec is as follows:
- Blitz Stainless Induction Kit
- D-Sport Low Temperature Thermostat
- SARD Fuel Pressure Regulator
- Blitz Spec R i-D Boost Controller
- Blitz Power i-D Meter
- D-Sport Radiator Cap
- D-Sport Oil Cap
- Stainless Steel Breather Filter
- Earthing Kit
- GoGoauto Turbo Back Stainless Steel Exhaust
- Powerflex Exhaust Mounts
- 15” Rota Grids with Yokohama Parada Tyres
- D-Sport Coilovers & Pillowball Mounts
- D-Sport Front Strut Brace
- C-Pillar Bar
- D-Sport Grooved Front Discs
- D-Sport Yellow Front Pads
- D-Sport Gear Knob
- DRS Mk1 Front Bumper
- DRS Side Skirts
- Clear Side Repeaters
- Recaro Driver/Recaro Passenger Seat
- Greddy 60mm Boost Gauge
- Razo Pedals
- Pioneer Double DIN CD/MD
- Philps Blue Vision Headlight/Side Bulbs
Also have the following to go on at some point:
- D-Sport Rear Drums
- Exedy Clutch
- Momo 'Race' Steering Wheel/Boss
- Blitz Horn Button
With the parts fitted, we took her down to see Martyn @ Engine Tuner. A quick check on the boost levels on the rolling road produced this:
Not bad for a 713cc eh?
The next hurdle to producing more power is to get more air to the engine via the Front Mounted Intercooler, and to sort add some form of fuel management. The Intercooler is hidden behind the numberplate (quite why DRS designed the bumper like that I've no idea!), so I intend to relocate the plate and remove the section behind this to allow more air to reach the Intercooler. Once I decide on what management to get for the fueling, the intention is to raise it to approximately 24psi (1.6bar). Hopefully, this should equate to something near to 150/160bhp.
This is how the car looks now:
Future plans include looking at getting the existing ECU remapped by a specialist in Japan, which will apparently be good for up to 32psi (2.2bar)!! Another area that is being investigated is a stainless/mild steel manifold. However, once past 24psi, cost starts to rise considerably as the valves and other bits need to be looked at, so I'm ensure about how far I really want to go.
Any further changes will be added here, so check back when your next passing!