For my Algodoo v2.1.3 I used the simulation speed of 4.0x. I already spoke with you in general discussion about my issues with not being able to insert a stopwatch into Algodoo. You said we have the option to use our own stopwatch and that is what I have been doing to calculate the equations. Unfortunatly, my calculations will not be as acurate as with using a stopwatch built into Algodoo, but it will get the job done.