Finally, we have managed to get the English version of the database working. The delay was caused since all the data was stored as text, and so a calculation of the different values was simply not possible. That's future oriented database design ;-) So we needed to convert the text values to numeric and then it was easy to calculate the different values (mp/h, mpg, torque)... I hope this makes it easier for the 'non metric' users to understand the database.