diff --git a/aichallenge/workspace/src/aichallenge_submit/aichallenge_submit_launch/launch/reference.launch.xml b/aichallenge/workspace/src/aichallenge_submit/aichallenge_submit_launch/launch/reference.launch.xml
index c8e8180c..8e2fe222 100644
--- a/aichallenge/workspace/src/aichallenge_submit/aichallenge_submit_launch/launch/reference.launch.xml
+++ b/aichallenge/workspace/src/aichallenge_submit/aichallenge_submit_launch/launch/reference.launch.xml
@@ -205,9 +205,9 @@
 
   <node pkg="simple_pure_pursuit" exec="simple_pure_pursuit" name="simple_pure_pursuit_node" output="screen">
     <param name="use_external_target_vel" value="true"/>
-    <param name="external_target_vel" value="12.0"/>
-    <param name="lookahead_gain" value="0.12"/>
-    <param name="lookahead_min_distance" value="1.5"/>
+    <param name="external_target_vel" value="8.0"/>
+    <param name="lookahead_gain" value="0.3"/>
+    <param name="lookahead_min_distance" value="4.0"/>
     <param name="speed_proportional_gain" value="1.0"/>
 
     <remap from="input/kinematics" to="/localization/kinematic_state"/>