What is all this stuff about "UFOs" for 5k or V8s? I admit that I am a dullwit when it comes to pre-96 Audi's. Also, what is the difference between 4k, 5k, V8, S4, 100, 200, etc... I am just clueless. Also, how can you run an engine at almost 2bar and still drive it everyday and have less than 400 hp? Sorry to be so ignorant, Dan