a barf bag with you the first time you slam on the brake.
Modified your PLR file with these values to enable head physics:
Glance Rate="10.00000"
Look Up/Down Angle="0.95000"
Leanahead Angle="0.20000"
Look Roll Angle="0.80000"
Glance Angle="0.60000"
Lookahead Angle="0.20000"
Head Physics="2.00000"
Head Rotation="2.00000"
Source: http://www.racesimcentral.net/~hg/forum/viewtopic.php?t=62707
&sid=e8af9961b208c03ff488b3ac0f870755