Arena Axes and Turn Delay
From Armagetron
Arena Axes
How many 'Arena Axes' there are defined determine how sharp you can turn. The default and classic number is four, which limits you to 90° turns. Server administrators define how many axes a game grid has. The more axes there are the less sharp your turns will be.
Turn Delay
How fast you can turn depends upon the 'Turn Delay' setting. It puts a minimum length of time that must occur between turns. This handicaps how quickly you can turn.