FUN FACT: No S-Type Rs ever actually made 390-400 hp. It was just a marketing ploy made by Jaguar to compete in the M5/E55 crowd. The fastest ones did around 13.8-14.0sec in the 1/4-mile at around 102mph average. The most powerful ones made around 330-360 hp at the crank. Not one acceleration test showed that the STR could rev to 6100 rpm, it was more like 5250-5500 rpm.
What was "supposed" to be an E39 M5 and W210/W211 E55 AMG rival, was really an E60 545i and W211 E500 Mk1 rival