I have received an e-mail asking about the differing opinions as to Poser units' values. This is one case where this does not matter. You are trying to achieve a believable speed for your vehicle, and a relative motion when compared to the rest of your scene, so that your wheels do not spin in one place, or move to slowly for the forward motion. So whatever scale and Poser utility you are using, your calculations will be correct, because you are calculating a relative motion. I will see if I can make an example using differing scales to show you that this does not matter.

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