What are the differences between a 1990 20V Ur Quattro and the USA Counter-part (1990 Quattro Coupe/ 20V Sedan)? How far can I take my 20V Sedan to the Ur model? > My 1990 20V Ur Quattro (Electronic Fuel Injection) has a Bosch ECU > that can be "Chipped" (Very Successfully I might add) by unplugging one > EPROM (chip) and plugging another one in.