diff --git a/device/event_model/common/include/States.cuh b/device/event_model/common/include/States.cuh
index f206d7140f3fdd38956794881968aaa4ce6c99fe..0efb6e9e039b28b0b4184db140c9fd42674c8a27 100644
--- a/device/event_model/common/include/States.cuh
+++ b/device/event_model/common/include/States.cuh
@@ -232,7 +232,10 @@ namespace Allen {
 
         __host__ __device__ float e(const float mass) const { return sqrtf(p() * p() + mass * mass); }
 
-        __host__ __device__ float eta() const { return atanhf(pz() / p()); }
+        __host__ __device__ float eta(bool isBackward=false) const
+        {
+          return isBackward ? -1.f * atanhf(pz() / p()) : atanhf(pz() / p());
+        }
 
         __host__ __device__ float rho() const { return sqrtf(tx() * tx() + ty() * ty()); }
 
diff --git a/device/event_model/velo/include/VeloDefinitions.cuh b/device/event_model/velo/include/VeloDefinitions.cuh
index 1fd1dc64e9f2c05b61e219f503a5b1a8fad2cbae..de00725388118052cb30efc205bb2fb670a608e2 100644
--- a/device/event_model/velo/include/VeloDefinitions.cuh
+++ b/device/event_model/velo/include/VeloDefinitions.cuh
@@ -77,11 +77,11 @@ namespace TimingVelo {
     static constexpr unsigned number_of_sensor_columns = n_chips_per_sensor * n_cols;
     static constexpr unsigned number_of_pixels_per_sensor = number_of_sensor_columns * n_rows;
 
-    static constexpr float z_endVelo = 800; // FIXME_GEOMETRY_HARDCODING
+    static constexpr float z_endVelo = 793.25; // FIXME_GEOMETRY_HARDCODING
 
     // Constants for requested storage on device
     static constexpr unsigned max_track_size = n_stations;
-    static constexpr unsigned max_tracks_to_follow = 2048;
+    static constexpr unsigned max_tracks_to_follow = 4096;
 
     static constexpr float pixel_size = 0.055f; // FIXME_GEOMETRY_HARDCODING
   } // namespace Constants
diff --git a/device/velo/simplified_kalman_filter/include/VeloKalmanFilter.cuh b/device/velo/simplified_kalman_filter/include/VeloKalmanFilter.cuh
index a6ab613486088f10d5a4be4dd7be5d1c729e98a1..33f3c482794d1d74aeb8bef5cd2e81f04cc56e73 100644
--- a/device/velo/simplified_kalman_filter/include/VeloKalmanFilter.cuh
+++ b/device/velo/simplified_kalman_filter/include/VeloKalmanFilter.cuh
@@ -156,7 +156,7 @@ namespace velo_kalman_filter {
                 (state.tx() * state.tx() + state.ty() * state.ty());
     }
     else {
-      // Propagate to the end of the Velo (z=770 mm)
+      // Propagate to the end of the Velo (z=800 mm)
       delta_z = TimingVelo::Constants::z_endVelo - state.z();
     }