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Oval Race Track v1.5

The last racer standing wins :D
Just for fun.
Also shows how to do a smoother loop for your own race track!

UPDATE:
"How To" video added.
You can see how I have placed the platforms. When finished, It is good to do a backup of your map. Then open the map using SEToolbox and convert all "big ship" entries into a "station", save it, and check it out inside Space Engineers. Finally you can delete (in game) all landing gear and useless blocks.
There is one important thing to keep in mind. If a block is placed on a platform (in game) subsequent to this process, the platform may experience strange behavior in its grid causing a change in its location and may have some misalignment.
SEToolbox:
http://forums.keenswh.com/post/custom-importereditor-tool-setoolbox-6638984

UPDATE v1.5
Box + 2 cars