Took some doing, but I did manage to get S3D running well with FLSun Super Racer. The biggest issue had to do with the filament runout sensor not working. It did work however with gcode from Cura. I went back to Cura briefly and discovered two things: Cura inserts an M82 (absolute E) at the start of the gcode, and does not zero out the extruder distance (G92E0) during the run. I was able to make Simplify3D mimic this behavior, and now the runout sensor works normally.
I am attaching my FFF file, it's set up for quick PLA printing.
Neil
Happy to say the FLSUN Super Racer is now present in the V5 configuration assistant. Just go to Help > Configuration Assistant and type the printer name. We did a lot of testing with this machine ourselves so the profile was performing quite well. Thanks for the request!