or we can do it this way

selfdrive/car/toyota/carstate.py

@@ -6,7 +6,7 @@ from opendbc.can.can_define import CANDefine
 from selfdrive.car.interfaces import CarStateBase
 from opendbc.can.parser import CANParser
 from selfdrive.config import Conversions as CV
-from selfdrive.car.toyota.values import ToyotaFlags, CAR, DBC, STEER_THRESHOLD, NO_STOP_TIMER_CAR, TSS2_CAR
+from selfdrive.car.toyota.values import ToyotaFlags, CAR, DBC, STEER_THRESHOLD, NO_STOP_TIMER_CAR, TSS2_CAR, EPS_SCALE
 
 
 class CarState(CarStateBase):
@@ -14,6 +14,7 @@ class CarState(CarStateBase):
     super().__init__(CP)
     can_define = CANDefine(DBC[CP.carFingerprint]["pt"])
     self.shifter_values = can_define.dv["GEAR_PACKET"]["GEAR"]
+    self.eps_torque_scale = EPS_SCALE.get(CP.carFingerprint, 73) / 100.
 
     # On cars with cp.vl["STEER_TORQUE_SENSOR"]["STEER_ANGLE"]
     # the signal is zeroed to where the steering angle is at start.
@@ -78,8 +79,7 @@ class CarState(CarStateBase):
     ret.rightBlinker = cp.vl["BLINKERS_STATE"]["TURN_SIGNALS"] == 2
 
     ret.steeringTorque = cp.vl["STEER_TORQUE_SENSOR"]["STEER_TORQUE_DRIVER"]
-    ret.steeringTorqueEps = cp.vl["STEER_TORQUE_SENSOR"]["STEER_TORQUE_EPS"] * \
-                            (self.CP.safetyConfigs[0].safetyParam / 100.)
+    ret.steeringTorqueEps = cp.vl["STEER_TORQUE_SENSOR"]["STEER_TORQUE_EPS"] * self.eps_torque_scale
     # we could use the override bit from dbc, but it's triggered at too high torque values
     ret.steeringPressed = abs(ret.steeringTorque) > STEER_THRESHOLD
     ret.steerWarning = cp.vl["EPS_STATUS"]["LKA_STATE"] not in (1, 5)

selfdrive/car/toyota/interface.py

@@ -2,7 +2,7 @@
 from cereal import car
 from selfdrive.config import Conversions as CV
 from selfdrive.car.toyota.tunes import LatTunes, LongTunes, set_long_tune, set_lat_tune
-from selfdrive.car.toyota.values import Ecu, CAR, ToyotaFlags, TSS2_CAR, NO_DSU_CAR, MIN_ACC_SPEED, CarControllerParams
+from selfdrive.car.toyota.values import Ecu, CAR, ToyotaFlags, TSS2_CAR, NO_DSU_CAR, MIN_ACC_SPEED, EPS_SCALE, CarControllerParams
 from selfdrive.car import STD_CARGO_KG, scale_rot_inertia, scale_tire_stiffness, gen_empty_fingerprint, get_safety_config
 from selfdrive.car.interfaces import CarInterfaceBase
 
@@ -27,10 +27,9 @@ class CarInterface(CarInterfaceBase):
     ret.stoppingControl = False  # Toyota starts braking more when it thinks you want to stop
 
     # Most cars use this default safety param
-    ret.safetyConfigs[0].safetyParam = 73
+    ret.safetyConfigs[0].safetyParam = EPS_SCALE.get(candidate, 73)
 
     if candidate == CAR.PRIUS:
-      ret.safetyConfigs[0].safetyParam = 66  # see conversion factor for STEER_TORQUE_EPS in dbc file
       stop_and_go = True
       ret.wheelbase = 2.70
       ret.steerRatio = 15.74   # unknown end-to-end spec
@@ -49,7 +48,6 @@ class CarInterface(CarInterfaceBase):
       set_lat_tune(ret.lateralTuning, LatTunes.LQR_RAV4)
 
     elif candidate == CAR.COROLLA:
-      ret.safetyConfigs[0].safetyParam = 88
       stop_and_go = False
       ret.wheelbase = 2.70
       ret.steerRatio = 18.27
@@ -154,7 +152,6 @@ class CarInterface(CarInterfaceBase):
       set_lat_tune(ret.lateralTuning, LatTunes.PID_J)
 
     elif candidate == CAR.LEXUS_IS:
-      ret.safetyConfigs[0].safetyParam = 77
       stop_and_go = False
       ret.wheelbase = 2.79908
       ret.steerRatio = 13.3
@@ -163,7 +160,6 @@ class CarInterface(CarInterfaceBase):
       set_lat_tune(ret.lateralTuning, LatTunes.PID_L)
 
     elif candidate == CAR.LEXUS_RC:
-      ret.safetyConfigs[0].safetyParam = 77
       stop_and_go = False
       ret.wheelbase = 2.73050
       ret.steerRatio = 13.3
@@ -172,7 +168,6 @@ class CarInterface(CarInterfaceBase):
       set_lat_tune(ret.lateralTuning, LatTunes.PID_L)
 
     elif candidate == CAR.LEXUS_CTH:
-      ret.safetyConfigs[0].safetyParam = 100
       stop_and_go = True
       ret.wheelbase = 2.60
       ret.steerRatio = 18.6

selfdrive/car/toyota/values.py

@@ -1684,6 +1684,8 @@ DBC = {
   CAR.ALPHARD_TSS2: dbc_dict('toyota_nodsu_pt_generated', 'toyota_tss2_adas'),
 }
 
+# These cars have non-standard EPS torque scale factors. All others are 73
+EPS_SCALE = {CAR.PRIUS: 66, CAR.COROLLA: 88, CAR.LEXUS_IS: 77, CAR.LEXUS_RC: 77, CAR.LEXUS_CTH: 100}
 
 # Toyota/Lexus Safety Sense 2.0 and 2.5
 TSS2_CAR = {CAR.RAV4_TSS2, CAR.COROLLA_TSS2, CAR.COROLLAH_TSS2, CAR.LEXUS_ES_TSS2, CAR.LEXUS_ESH_TSS2, CAR.RAV4H_TSS2,