It is important to understand the basic principles of engine design as this has a bearing upon bio-fuels as well as other fuels, and their relationship to differing fuel standards around the world.
Engines cost millions to develop, they are designed perform under a wide range of conditions, and be reasonably reliable, manufacturers make no money from reliable engines, so incorporate a few niceties to make us take them to the dealers for servicing, i.e. common rail fuel injection.
Prior to the harmonisation of fuel standards in Europe, the European markets presented engine designers with many challenges, each country had its own fuel standards, and engines had to be made for each market to allow them to run on these fuels available. This could be explained simply as those of us of a certain age who travelled around Europe by car would often carry fuel additives for use in different countries, we had cars with engines designed to run on U.K. fuel. Spain had notoriously bad fuel, if we travelled there we would carry sufficient additives to add to the fuel, or be faced with mechanical breakdowns, or at the very least the cylinder head would come off and valves and valve seats would have to be replaced.
Manufacturers would build one car, this may have as many as eight different engines fitted for the European market alone, add into the equation, the many world markets in which one model of car was sold and there were many more engines having to be developed and produced. These engines were known as specific market produced.
Harmonisation of fuel standards meant that one vehicle could be produced with one engine for Europe alone, this gave the car makers a lot less engine development work, and considerable cost savings, cheaper cars, and most importantly, more profit.
Two Japanese manufacturers, Toyota and Nissan had large vehicle sales in the African, Australasia, and Asian markets, due to trade agreements they sold relatively few vehicles in the European markets. Developing one engine for these markets meant developing engines which would operate on poor fuel, they were well developed and operated reliably under these conditions, time and money went into their engine development programmes. Both companies were the early pioneers of engines designed for the world market, one engine designed to operate in the harshest conditions, meet all emissions regulations in place such as those in Japan or America, and be sold anywhere in the world.
Enter Toyota, they had a stake in Daihatsu, they designed and developed a 2.5 litre light truck diesel engine, this was a “world” engine, it met emissions standards in countries which had them, was durable, and most importantly, reliable and cheap to use. Daihatsu had access to the parts which Toyota produced; Toyota decided not to use this engine, but Daihatsu adopted it for the F50 model and other Asian market commercial vehicles. Toyota continued to develop this engine alongside Daihatsu; the result was another world engine, the 2.8 litre diesel, this engine was available in a range of power outputs from 70-160 B.H.P. in normally aspirated and turbocharged form. This engine was used in vehicles, boats in higher outputs, and even as static industrial engines, a testament to its excellent design is that it was in production virtually unchanged for over forty years. Now, virtually all engines produced by all manufacturers are world engines, one engine sold in every world market; tuning these engines to run on good quality, or poor quality fuels is simply a matter of reprogramming the ECU with a different programme for the specific market.