Sorry to skite, as kei cars are as rare as hens teeth over your way...I have just purchased a 2004 5 door Daihatsu Charade with only 39,000km from an elderly couple
Its a 3cylinder 1000cc 58bhp 5 speed with a super long intake manifold to boost low end torque, no vvt on my model, and has very low emissions as has a catalytic converter. CD 0.31 weight 740kg.
Some spec pages here:
2003 Daihatsu Charade SL technical specifications and data - 5 door 1 litre (989 cc) S3 58.8 PS - Carfolio.com car specifications pages
First calculation I got 4.4l/100km with much a/c and 100km/hr (65mph)
Next calculation it returned 4l/100km. I ran 50psi from the moment I took possession.
I hope to consistently get around 3.2l/100km @50mph (around 70mpgUS) after installing a kill switch and modifying the front grill area.
I have some questions about fooling the ecu, an area I know nothing about.
Overall I'm happy with it except in handles poorly on the bumpy twisty roads going out to the beaches near me. Very, very narrow car with a high roof....creates an uneasy and unpredictable response. The engine response with the extra long intake manifold is great for hypermiling. 4th and 5th gears are very long to so no need to modify ratios for economy, already done.
I'm looking into an alloy wheel with a greater offset or spacer, and fitting stiffer walled 165's instead of the 155 tires (I realise thats not a ecomodder thing to do but I'm spoilt for handling after years with Citroen and Peugeot). Hopefully this mod to wheels will mitigate the poor handling and cornering.
My first Daihatsu and so much cheaper to buy than a Honda or Toyota