diff --git a/y3prediction/prediction.py b/y3prediction/prediction.py
index 7dd9d08..171e813 100644
--- a/y3prediction/prediction.py
+++ b/y3prediction/prediction.py
@@ -2683,6 +2683,7 @@ def inlet_ramp_pressure(t):
             dim=dim,
             nspecies=nspecies,
             disc_sigma=500.,
+            disc_loc=shock_loc_x,
             pressure_bulk=pres_bkrnd,
             temperature_bulk=temp_bkrnd,
             velocity_bulk=vel_outflow,
@@ -5032,15 +5033,13 @@ def inflow_ramp_pressure(t):
                     mach=inlet_mach,
                     p_fun=inflow_ramp_pressure)
             else:
-                smooth_r0 = fluid_nodes
-                smooth_r0[1] = actx.np.zeros_like(fluid_nodes[0])
-                smooth_r0[2] = actx.np.zeros_like(fluid_nodes[0])
+                r0 = np.zeros(shape=(dim,))
                 inflow_state = IsentropicInflow(
                     dim=dim,
                     temp_wall=temp_wall,
                     temp_sigma=temp_sigma,
                     vel_sigma=vel_sigma,
-                    smooth_r0=smooth_r0,
+                    smooth_r0=r0,
                     smooth_r1=0.013,
                     normal_dir=normal_dir,
                     gamma=gamma,
@@ -5415,15 +5414,13 @@ def _sponge_sigma(sponge_field, x_vec):
                                             thickness=outlet_sponge_thickness,
                                             amplitude=sponge_amp,
                                             direction=1)
-            #sponge_init_top = InitSponge(x0=top_sponge_x0,
-                                         #thickness=top_sponge_thickness,
-                                         #amplitude=sponge_amp,
-                                         #direction=1)
 
         def _sponge_sigma(sponge_field, x_vec):
             sponge_field = sponge_init_outlet(sponge_field=sponge_field, x_vec=x_vec)
             sponge_field = sponge_init_inlet(sponge_field=sponge_field, x_vec=x_vec)
-            sponge_field = sponge_init_top(sponge_field=sponge_field, x_vec=x_vec)
+            if dim == 2:
+                sponge_field = sponge_init_top(
+                    sponge_field=sponge_field, x_vec=x_vec)
             return sponge_field
 
     sponge_sigma = actx.np.zeros_like(restart_cv.mass)
@@ -5948,7 +5945,6 @@ def my_write_viz(step, t, t_wall, viz_state, viz_dv,
         if viz_level > 2:
 
             if use_species_limiter:
-                print(f"{theta_rho.shape=}")
                 viz_ext = [("theta_rho", theta_rho),
                            ("theta_Y", theta_Y),
                            ("theta_pressure", theta_pres)]
diff --git a/y3prediction/unstart.py b/y3prediction/unstart.py
index aaa414d..f5e6ea5 100644
--- a/y3prediction/unstart.py
+++ b/y3prediction/unstart.py
@@ -19,7 +19,7 @@ class InitUnstartRamp:
     .. automethod:: add_injection
     """
 
-    def __init__(self, *, dim=2, nspecies=0, disc_sigma,
+    def __init__(self, *, dim=2, nspecies=0, disc_sigma, disc_loc,
                  pressure_bulk, temperature_bulk, velocity_bulk,
                  mass_frac_bulk,
                  pressure_inlet, temperature_inlet, velocity_inlet,
@@ -44,6 +44,7 @@ def __init__(self, *, dim=2, nspecies=0, disc_sigma,
         self._dim = dim
         self._nspecies = nspecies
         self._disc_sigma = disc_sigma
+        self._disc_loc = disc_loc
         self._temp_wall = temp_wall
         self._temp_sigma = temp_sigma
         self._vel_sigma = vel_sigma
@@ -135,7 +136,7 @@ def inlet_smoothing_func(self, x_vec, sigma):
         else:
             r1 = 0.013
             radius = actx.np.sqrt((x_vec[1])**2 + (x_vec[2])**2)
-            smth_radial = smooth_step(actx, -sigma*(radius - r1))
+            smth_radial = smooth_step(actx, sigma*actx.np.abs(radius - r1))
             return smth_radial
 
     def outlet_smoothing_func(self, x_vec, sigma):
@@ -150,7 +151,7 @@ def outlet_smoothing_func(self, x_vec, sigma):
         else:
             r1 = 0.2
             radius = actx.np.sqrt((x_vec[1])**2 + (x_vec[2])**2)
-            smth_radial = smooth_step(actx, -sigma*(radius - r1))
+            smth_radial = smooth_step(actx, sigma*actx.np.abs(radius - r1))
             return smth_radial
 
     def add_inlet(self, cv, pressure, temperature, x_vec, eos, *, time=0.0):
@@ -183,11 +184,9 @@ def add_inlet(self, cv, pressure, temperature, x_vec, eos, *, time=0.0):
 
         # initial discontinuity location
         if self._dim == 2:
-            y0 = -0.325
-            dist = y0 - x_vec[1]
+            dist = self._disc_loc - x_vec[1]
         else:
-            x0 = -0.325
-            dist = x0 - x_vec[0]
+            dist = self._disc_loc - x_vec[0]
 
         # now solve for T, P, velocity
         xtanh = self._disc_sigma*dist
diff --git a/y3prediction/utils.py b/y3prediction/utils.py
index c8dc152..b46e4e3 100644
--- a/y3prediction/utils.py
+++ b/y3prediction/utils.py
@@ -508,7 +508,6 @@ def __init__(self, *, dim, T0, P0, mass_frac, mach, gamma,
         self._x0 = smooth_x0
         self._y0 = smooth_y0
         self._z0 = smooth_z0
-        self._r0 = smooth_r0
         self._x1 = smooth_x1
         self._y1 = smooth_y1
         self._z1 = smooth_z1
@@ -517,6 +516,8 @@ def __init__(self, *, dim, T0, P0, mass_frac, mach, gamma,
         if smooth_r0 is None:
             self._r0 = np.zeros(shape=(dim,))
             self._r0[0] = 1
+        else:
+            self._r0 = smooth_r0
 
         if normal_dir is None:
             self._normal_dir = np.zeros(shape=(dim,))