A look at the most unlikely performance cars you'd ever imagine - the Japanese Kei class turbo guns!
By Michael Knowling

For those unaware, Kei cars are vehicles that meet certain body dimensions, engine capacity and power

The first group of Kei cars were limited to 360cc engines (including 2-strokes!), but this later grew to 4-stroke 550cc motors (with a maximum of 42ps or 31kW) and then - as you'll see - 660cc motors (with up to 64ps or 47kW).
So let's now take a look at the Kei performance cars in chronological order...
The Emerging 550cc Terrors
Prior to the introduction of the Kei class performance cars, it was Honda in 1982 that offered the nearest thing - the Honda City Turbo. Powered by an ER-series SOHC, 1.3-litre four-cylinder - with just a 7.5:1 compression ratio - the 'bulldog' look Honda pumped out a creditable 74kW at 5500 rpm along with 147Nm of torque at 3000 rpm. No question, the little Honda scooted its 690-kilogram kerb mass quite capably.
Although still considerably larger than a Kei class vehicle, it was Nissan that took small car

Daihatsu, meanwhile, was heading further in the direction of what would eventually be the Kei high performance class. Its 1983 released G11 Charade turbo used a three-cylinder engine of just 993cc and - equipped with an IHI turbo blowing through a carburettor - it was rated at 59kW at 5500 rpm and 118Nm at 3500. Like the Honda and Nissan, the Charade turbo ran without any form of intercooling.
The turbo Charade was released as both a 4-door hatch (as delivered to Australia) and a 2-door hatch, with kurb weights of just 685 to 720 kilograms. A DeTomaso version - with the same output - was released in latter years.

MMC - Mitsubishi Motors Corporation - was next on the bandwagon with its hot Minica. Available only as a two-door, the Minica used a G23B SOHC carburetted 546cc three-pot with a 8.5:1 compression ratio, good for 30kW and 57Nm at 6000 and 3500 rpm respectively. The weight of the Minica? Just 560 kilograms!
Subaru and Suzuki were the next manufacturers to recognise the demand for pint-size cars with squirt.

Suzuki, meanwhile, challenged with its new Cervo turbo - another 2-door only hatchback. Using a SOHC F5A 543cc three, the little Suzuki spat out a mild 29kW at 6000 and 54Nm at 4000 rpm. Interestingly, the same engine was mounted longitudinally in the Suzuki Jimny (aka Sierra) off-road 4WD.


Again, a 'high-rise' 4WD turbo version - with a more basic live rear axle - was released the year after the L70's initial release; think of a full-scale Tonka toy and that's pretty well what this vehicles looks like...
The power war was surely on by this stage.
It wasn't long before Suzuki churned out its first Alto RS. With a F5A SOHC 550cc motor ticking under the bonnet, the Alto RS put out a substantial 35kW at 6000 rpm, but with a relatively modest 64Nm at 4000 rpm. The RS was a front-wheel-drive 2-door weighing just 580 kilograms, while a 4WD version - the Alto SX - added a further 60 kay-gees.

The EB 547cc motor in the Mira TRX-X from late '88 got bumped up to a class-leading 43kW at 6500 rpm and a very sunny 73Nm at 4000 rpm. Weight was still kept down to under 600kg in both the front and optional four-wheel-drive models.
Also at this time, Daihatsu replaced the G11 Charade turbo - with its SOHC carby turbo motor -with the larger G100 Charade GTX-X boasting an awesome DOHC, 12-valve, EFI, 993cc three-pot putting out an incredible 77kW at 6500 rpm and 130Nm of torque at 3500 rpm. It's no wonder this little slogger went on to considerable rally success.
Mightier Midgets!

The new era of Kei performance kicked off with vehicles such as the revised L200 Daihatsu Mira Turbo. Sporting a new EF-JL 659cc three-cylinder with a SOHC, 12-valve head, EFI and a small top-mount air-to-air intercooler, the revised monster Mira made the regulation 47kW at a high 7500 rpm plus 92Nm at 4000 rpm. The new Mira was available in both 2 and 4-door hatchback form and came with optional 4WD and 4WS.
Subaru's Rex underwent a dramatic change with the new regulations. Oddly, it ignored any allowable increase in capacity and, instead, exchanged its turbocharger for a little positive displacement supercharger fitted to a new EN05 SOHC 547cc mill running EFI, an intercooler and a 8.5:1 compression ratio. Output was 45kW at 6400 rpm and 75Nm of torque at 4400 rpm. All-wheel-drive was, of course, available to buyers.

For 1991, the Alto Works' engine was swapped to something a little more serious - a 658cc F6A DOHC design, which allowed the 47kW max output to be attained at lower revs - 6500 - as well as a strong 90Nm of torque at 4000 rpm.
The 'non Works' turbo version of the Alto, meanwhile, used a slightly less grunty 657cc DOHC F6B engine.

A new 'bubble' Minica hit the streets in 1993 employing a new generation 4A30 659cc, DOHC turbo intercooled motor cranking out, of course, 47kW at 7000 rpm and a mammoth 97Nm at 3500 rpm. Weight though, had crept up to 780 kilograms.

Rex got bitten, though, when the Subaru Vivio replaced it in 1993. The 730-kilogram Vivio featured much better design and retained the EN07 supercharged engine with the same outputs. A model change in later years saw a boost to 90Nm at 4000 rpm.
How Fast?
You may be wondering how fast the little Kei class rockets are. Well, given the 660cc examples are all limited to 47kW and hover around 750 kilograms in mass, they're all pretty well line-ball in straight-line acceleration - expect 9 - 10-second 0 - 100s, with mid-ish 16-second quarter miles.
But there's no reason to stop there...
With minimal weight to haul around, even relatively small power-ups can give these cars a sizeable increase in performance. Add a high-flow exhaust, air intake, enhance the intercooling and up the boost and you've got an easy low 15 flier. We've even seen some of these beasts crack into the 13s with standard internals!
Y-eah!


Note that the 1993 Suzuki Alto Works RS/R also benefited from fitment of the new K6A at the same time, making it the undisputed King of Kei hatches.

The Daihatsu Max and Opti also came out with an EF-DET 649cc, DOHC, 12-valve turbo with 47,000W and an outstanding 107Nm of torque - the highest we've seen from any Kei car.
The new Atari wagon and updated Move RS Limited got the same engine to propel its 860-odd kilogram mass. The Daihatsu Terios 'Kid' and Naked wagon (don't ask!) are also endowed with 649cc turbo power.


Also in the Suzuki stable is the creatively named Kei, which is based on the Alto; the K6A engine is also available in this vehicle.

With the huge selection of Kei performance engines and complete cars available for a relative pittance outa Japan, we reckon there's no good reason to overlook them; just imagine the satisfaction of chopping your neighbour's HSV with a souped-up shopping trolley!
So go on - either drop a turbo (or supercharged) import engine into a locally delivered small-car or nag your local Japanese importer to bring you a complete car for compliance. Do whatever it takes!