Red Herring wrote:As said earlier in order to maintain safety manufactures fit ESP and such like. What we found on the BMW M3 is that in anything other than fast dry conditions the car is continually being restricted by the ESP. You need to remember that the majority of police pursuits don't take place on the Motorway, they are 1st, 2nd and 3rd gear action on confined roads and powerful two wheel drive cars just end up living on their ESP, or generating lots of smoke.....A good pursuit car needs a top speed of around 150mph, but the way it gets between 30 and 90 will make all the difference to safety.
General points completely accepted and understood, but I am disappointed by the results of your tests. My personal experience is that you can use nearly all of the current M3's power even on streaming wet B roads, only breaking traction if you use full-throttle exiting a tight second gear bend when the ESP will rein you in. Some experienced friends and I drove M3, C63 and RS4 in a wet North Wales, and concluded that even with this much power and in those conditions there was little benefit from 4 wheel drive. I would have expected an M3 to be suitable for such duties, though I have no idea about comparative running costs.