Is there a right and wrong way to sit on a long journey

upright, your wrists should sit on top of the steering wheel when you put your arms out in front of you.
 
lean back as far as possible, then if you get tired you can stick cruise control on and get a passenger to steer while you take a 5 minute power nap.

On a serious note, whatever you feel the most comfortable with. Im in the middle of being bolt upright and leaning back
 
Put the seat back so far back you can hardly reach the wheel. Always only drive with one hand. This looks cool :d

Also if you hit into something backwards hard you turn into a human missile.
 
My seating position is always bolt upright, gives you the best chance to react to anything I believe, if your laid back chilling out not concentrating is how accidents happen!
 
Put the seat back so far back you can hardly reach the wheel. Always only drive with one hand. This looks cool :d

Also if you hit into something backwards hard you turn into a human missile.
Agreed. This is much more comfortable on a long journey. Easier to sit back and read something to pass the time
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