The Mazda FD RX-7's are very tricky to tune and drive. They have a real tendency to mid-corner oversteer under deceleration.
I found even brake settings (11/11 or 12/12) helped[*], together with keeping ride height sufficiently high that the suspension still worked (109mm/109mm I believe) and doing the recommended tweaks to cause a little understeer (slightly stiffer front than rear for springs and stabilizers). Eventually I found them enjoyable to drive in the Hard-Tuned series.
For the Normal series, you must just practise, practise, practise until you have sympathy with the car and can feel what the weight distribution is doing as you drive around the corners.
Another fun FR car for the Hard-Tuned series is the Nissan 180SX'94.
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[*] Usually I use 12F/9R. Now, you would think that would correct deceleration oversteer, but it didn't seem to. Backing off to even settings seemed to result in better, more predictable balance of the whole car.