diff --git a/bin/OpenSimDefaults.ini b/bin/OpenSimDefaults.ini
index 8a451ecdad..e9bdabc7fe 100644
--- a/bin/OpenSimDefaults.ini
+++ b/bin/OpenSimDefaults.ini
@@ -221,10 +221,10 @@
     ; to false if you have compatibility problems.
     ;CacheSculptMaps = true
     
-    ; Choose one of the physics engines below
-    ; OpenDynamicsEngine is by some distance the most developed physics engine
-    ; basicphysics effectively does not model physics at all, making all objects phantom
-
+    ; Choose one of the physics engines below.
+    ; OpenDynamicsEngine is by some distance the most developed physics engine.
+    ; BulletSim is a high performance, up-and-coming physics engine.
+    ; basicphysics effectively does not model physics at all, making all objects phantom.
     physics = OpenDynamicsEngine
     ;physics = basicphysics
     ;physics = POS
@@ -908,15 +908,18 @@
 
 [BulletSim]
     ; World parameters
-    DefaultFriction = 0.50
+    DefaultFriction = 0.20
     DefaultDensity = 10.000006836
     DefaultRestitution = 0.0
     Gravity = -9.80665
 
-    TerrainFriction = 0.50
-    TerrainHitFriction = 0.8
+    TerrainFriction = 0.30
+    TerrainHitFraction = 0.8
     TerrainRestitution = 0
+    TerrainCollisionMargin = 0.04
+
     AvatarFriction = 0.2
+    AvatarStandingFriction = 0.99
     AvatarRestitution = 0.0
     AvatarDensity = 60.0
     AvatarCapsuleWidth = 0.6
@@ -930,27 +933,15 @@
     LinearDamping = 0.0
     AngularDamping = 0.0
     DeactivationTime = 0.2
-    LinearSleepingThreshold = 0.8
-    AngularSleepingThreshold = 1.0
-    CcdMotionThreshold = 0.0
-    CcdSweptSphereRadius = 0.0
-    ContactProcessingThreshold = 0.1
-    ; If setting a pool size, also disable dynamic allocation (default pool size is 4096 with dynamic alloc)
-    MaxPersistantManifoldPoolSize = 0
-    ShouldDisableContactPoolDynamicAllocation = False
-    ShouldForceUpdateAllAabbs = False
-    ShouldRandomizeSolverOrder = True
-    ShouldSplitSimulationIslands = True
-    ShouldEnableFrictionCaching = False
-    NumberOfSolverIterations = 0   
+    CollisionMargin = 0.04
 
     ; Linkset constraint parameters
+    LinkImplementation = 1      ; 0=constraint, 1=compound
     LinkConstraintUseFrameOffset = False
     LinkConstraintEnableTransMotor = True
     LinkConstraintTransMotorMaxVel = 5.0
     LinkConstraintTransMotorMaxForce = 0.1
 
-
     ; Whether to mesh sculpties
     MeshSculptedPrim = true