diff --git a/test/sample/testspeed_test.sh b/test/sample/testspeed_test.sh
index 942c2a98..f48342bc 100755
--- a/test/sample/testspeed_test.sh
+++ b/test/sample/testspeed_test.sh
@@ -26,8 +26,17 @@ test_model() {
   echo "Testing $model" >&2
 
   local iterations=10
-  if [[ "$model" == */composite/particle.xml && ${TESTSPEED_ASAN:-0} != 0 ]]; then
-    iterations=2
+  # for particularly slow models, only run 2 steps under ASAN, or skip.
+  if [[ ${TESTSPEED_ASAN:-0} != 0 ]]; then
+    if [[ "$model" == */composite/particle.xml ]]; then
+      # this test can take several minutes under ASAN
+      return 0
+    fi
+    if [[ "$model" == */benchmark/testdata/humanoid200.xml
+        || "$model" == */engine/testdata/collision_convex/stacked_boxes.xml
+    ]]; then
+      iterations=2
+    fi
   fi
 
   # run testspeed, writing its output to stderr.