Yes, I've tried and it cannot be done less than the top of N300.
I've come up with a stable tune for the RX500 using the DS4 controller with using the L/R sticks as steering and throttle / brakes.
Choice of tires is optional but the RS on front and RSS on rear gave me the best stable handling in the turns.
Not much has been changed from the stock settings with exception that I dropped the height to bottom, added 10 points to the F/R frequency, and changed the LSD to 50 50 50.
See enclosed pics
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View attachment 1069427
Hope this helps, with clean race you can easily clear 345,000 or so.