diff --git a/src/utils/cart_grid.cpp b/src/utils/cart_grid.cpp
index cb89cdca..f0e0e1a3 100644
--- a/src/utils/cart_grid.cpp
+++ b/src/utils/cart_grid.cpp
@@ -22,7 +22,7 @@
 // constructor, initializes data structures and parameters
 
 CartesianGrid::CartesianGrid(MeshBlockPack *pmy_pack, Real center[3],
-                                    Real extend[3], int numpoints[3], bool is_cheb):
+                                    Real extent[3], int numpoints[3], bool is_cheb):
     pmy_pack(pmy_pack),
     interp_indcs("interp_indcs",1,1,1,1),
     interp_wghts("interp_wghts",1,1,1,1,1),
@@ -37,19 +37,19 @@ CartesianGrid::CartesianGrid(MeshBlockPack *pmy_pack, Real center[3],
   center_x3 = center[2];
 
   // grid center
-  extend_x1 = extend[0];
-  extend_x2 = extend[1];
-  extend_x3 = extend[2];
+  extent_x1 = extent[0];
+  extent_x2 = extent[1];
+  extent_x3 = extent[2];
 
   // lower bound
-  min_x1 = center_x1 - extend_x1;
-  min_x2 = center_x2 - extend_x2;
-  min_x3 = center_x3 - extend_x3;
+  min_x1 = center_x1 - extent_x1;
+  min_x2 = center_x2 - extent_x2;
+  min_x3 = center_x3 - extent_x3;
 
   // upper bound
-  max_x1 = center_x1 + extend_x1;
-  max_x2 = center_x2 + extend_x2;
-  max_x3 = center_x3 + extend_x3;
+  max_x1 = center_x1 + extent_x1;
+  max_x2 = center_x2 + extent_x2;
+  max_x3 = center_x3 + extent_x3;
 
   // number of points
   nx1 = numpoints[0];
@@ -83,14 +83,40 @@ void CartesianGrid::ResetCenter(Real center[3]) {
   center_x3 = center[2];
 
   // lower bound
-  min_x1 = center_x1 - extend_x1;
-  min_x2 = center_x2 - extend_x2;
-  min_x3 = center_x3 - extend_x3;
+  min_x1 = center_x1 - extent_x1;
+  min_x2 = center_x2 - extent_x2;
+  min_x3 = center_x3 - extent_x3;
 
   // upper bound
-  max_x1 = center_x1 + extend_x1;
-  max_x2 = center_x2 + extend_x2;
-  max_x3 = center_x3 + extend_x3;
+  max_x1 = center_x1 + extent_x1;
+  max_x2 = center_x2 + extent_x2;
+  max_x3 = center_x3 + extent_x3;
+
+  SetInterpolationIndices();
+  SetInterpolationWeights();
+}
+
+void CartesianGrid::ResetCenterAndExtent(Real center[3], Real extent[3]) {
+  // grid center
+  center_x1 = center[0];
+  center_x2 = center[1];
+  center_x3 = center[2];
+
+  // grid extent
+  extent_x1 = extent[0];
+  extent_x2 = extent[1];
+  extent_x3 = extent[2];
+
+  // lower bound
+  min_x1 = center_x1 - extent_x1;
+  min_x2 = center_x2 - extent_x2;
+  min_x3 = center_x3 - extent_x3;
+
+  // upper bound
+  max_x1 = center_x1 + extent_x1;
+  max_x2 = center_x2 + extent_x2;
+  max_x3 = center_x3 + extent_x3;
+
   SetInterpolationIndices();
   SetInterpolationWeights();
 }
@@ -108,9 +134,9 @@ void CartesianGrid::SetInterpolationIndices() {
         Real x2 = min_x2 + ny * d_x2;
         Real x3 = min_x3 + nz * d_x3;
         if (is_cheby) {
-          x1 = center_x1 + extend_x1*std::cos(nx*M_PI/(nx1-1));
-          x2 = center_x2 + extend_x2*std::cos(ny*M_PI/(nx2-1));
-          x3 = center_x3 + extend_x3*std::cos(nz*M_PI/(nx3-1));
+          x1 = center_x1 + extent_x1*std::cos(nx*M_PI/(nx1-1));
+          x2 = center_x2 + extent_x2*std::cos(ny*M_PI/(nx2-1));
+          x3 = center_x3 + extent_x3*std::cos(nz*M_PI/(nx3-1));
         }
         // indices default to -1 if point does not reside in this MeshBlockPack
         iindcs.h_view(nx,ny,nz,0) = -1;
diff --git a/src/utils/cart_grid.hpp b/src/utils/cart_grid.hpp
index 01c53d23..c0642272 100644
--- a/src/utils/cart_grid.hpp
+++ b/src/utils/cart_grid.hpp
@@ -21,7 +21,7 @@ class CartesianGrid {
  public:
   // Creates a geodesic grid with refinement level nlev and radius rad
   CartesianGrid(MeshBlockPack *pmy_pack, Real center[3],
-                    Real extend[3], int numpoints[3], bool is_cheb = false);
+                    Real extent[3], int numpoints[3], bool is_cheb = false);
   ~CartesianGrid();
 
   // parameters for the grid
@@ -30,7 +30,7 @@ class CartesianGrid {
   Real max_x1, max_x2, max_x3;            // max value for xyz
   Real d_x1, d_x2, d_x3;                     // resolution
   int nx1, nx2, nx3;                      // number of points
-  Real extend_x1, extend_x2, extend_x3;
+  Real extent_x1, extent_x2, extent_x3;
 
   // dump on chebyshev or uniform grid, default is uniform
   bool is_cheby;
@@ -39,6 +39,7 @@ class CartesianGrid {
   DualArray3D<Real> interp_vals;   // container for data interpolated to sphere
   void InterpolateToGrid(int nvars, DvceArray5D<Real> &val);  // interpolate to sphere
   void ResetCenter(Real center[3]);  // set indexing for interpolation
+  void ResetCenterAndExtent(Real center[3], Real extent[3]);
 
  private:
   MeshBlockPack* pmy_pack;  // ptr to MeshBlockPack containing this Hydro