I was driving a stock 250f 6c. Here's where I originally posted the video...
http://www.assettocorsa.net/forum/index.php?threads/can-you-beat-fangios-world-record.41770/
I just had a go and I'm currently about to upload a vid of the new world record on rsrtiming app (it'll probably take 2-3 hours).
Here's the tune that I used:
Maserati 250f 6c
Gears 7/31
Tires stock (30 psi)
Fuel 12l
Camber 1 deg
Toe stock (-108)
Dampers stock
Brake bias 76%
Brake power stock (100%)
Suspension stock except lowered ride hieght to 13 on fronts 38 on rears
Throttle modulation is everything in this car because it controls the weight balance and controlling that weight shift is critical to get the car to do what you want rather than what it wants.
So a slight lift to get the front wheels to 'bite' and get the front turning in, then roll on the throttle to keep the back end in check and also so you don't spin the tires and loose momentum on corner exit. Slow in, fast out.
Two foot braking to keep the back tires from locking up while downshifting.
Slow is fast in this car. sliding sideways is slow but feels fast.
I'm sure you know all of this stuff but this car shows you how important driving technique actually is because it doesn't have any technology that compensates for poor driving tech, like modern fat tires with lots of grip, or disc brakes, or traction control or stability control - as far as I'm concerned this is the ultimate driving machine in ac.