You didn't say which physics, I have one for GNS that I have worked on, it's not perfected but we did use it at Bear Bait Racing for a league race that seemed to work pretty good, GNS physics, gotta watch the RF tire closely, the track eats tires pretty quick.
Couldn't attach a .sim file so I zipped it, you will have to unzip it to use it of course.
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