I wrote this recently in another thread.
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Wheel size matters.
http://www.wiki.cataclysmdda.com/index.php?title=Vehicles (note the links to more articles in upper right corner)
http://www.wiki.cataclysmdda.com/index.php?title=Making_a_Supercar:_Guide
http://www.wiki.cataclysmdda.com/index.php?title=Vehicle_parts
From “Vehicle Parts” above:
[i]Ideal wheel configuration depends mostly on the vehicle’s mass. When trying to maximize safe speed, total wheel area should be ~1.58 sqrt( mass ). Here “sqrt” means square root and mass is in kilograms.
Increasing the wheel area above that may increase acceleration, but it will decrease safe speed and thus also maximum speed and fuel economy.
For example, a 2500 kg (5512 lbs) truck should have a total wheel area of around 79. This can be achieved by installing just a single maximum sized armored wheel (20 width * 36 diameter / 9 = 80 area). The truck still needs more than one wheel to move, but the second wheel can be just a set of casters.[/i]
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