I think you will like the mambas I would recomed that you download the new version of the software off of the castle creations web site. Its smoother than the software that will come with the systems. As far as gearing I would recommend using the 4600 or the 5700 depending on how big of a track your running on. With the 4600 I would say 18-19 and with the 5700 16-17.
Hope this helps I would run them for 2-3 minutes and then check motor temps.
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