Very nice, one of my favorites. May I ask what you did to squeeze so much power of out of it? Had a 2002 540 that I would find excuses to go for a drive. I'm looking for an E39 M5, but prices are getting ridiculous for low mileage ones.
Stroker crank and 1st overbore, CP pistons with Scat rods, 10.5/1 compression. Megasquirt MS3 Pro engine management and bigger injectors. Tuned by a friend who really knows his stuff. He was surprised at the result, especially as it is breathing through the stock airbox with a stock BMW filter, and a stock exhaust system. The Euro cars were not built with cat converters, but were retrofitted when they were imported. This one is cat less, as BMW originally designed it.