--- a/src/physics/collision.rs
+++ b/src/physics/collision.rs
@@ -329,6 +329,7 @@
     contacts: &mut Vec<Contact>,
 ) {
     contacts.clear();
+    scratch.collided_shapes.clear();
     let (sx, sy) = cfg.shape_basis;
     let basis_x = V2::from(body_basis.0 * sx.x + body_basis.1 * sx.y);
     let basis_y = V2::from(body_basis.0 * sy.x + body_basis.1 * sy.y);
@@ -483,6 +484,8 @@
         if separated || push == V2::ZERO {
             continue;
         }
+        // SAT overlap keeps cached contacts eligible even without a new contact.
+        scratch.collided_shapes.push(shape_index);
         let support_car = rectangle_supports(&car, -push, basis_x, basis_y);
         let support_wall = polygon_supports(wall, shape, push);
         let mut pairs = [(V2::ZERO, V2::ZERO); 2];
@@ -601,11 +604,7 @@
     }
     find_contacts_with_basis(cfg, track, position, rotation, body_basis, scratch, contacts);
     previous.retain(|c| scratch.broad_pairs.contains(&c.shape_index));
-    scratch.collided_shapes.clear();
     for new in contacts.iter() {
-        if !scratch.collided_shapes.contains(&new.shape_index) {
-            scratch.collided_shapes.push(new.shape_index);
-        }
         let radius2 = (cfg.contact_recycle_radius as f32).powi(2);
         if let Some(old) = previous.iter_mut().find(|old| {
             let a = F2::from(old.local_point) - F2::from(new.local_point);
--- a/gpu/sim/step.h
+++ b/gpu/sim/step.h
@@ -471,7 +471,8 @@
 }
 
 // The rest of `solve_wall_contacts` once this tick's contacts are merged;
-// `made_contacts` has a bit per broad pair that made contacts.
+// `made_contacts` has a bit per SAT-overlapping broad pair, including
+// overlaps with no new points but a valid retained contact.
 __device__ inline SolveResult solve_contacts(const World& w, const VehicleDesc& v, Car& car, uint32_t made_contacts, Vec2 velocity,
                                              float angular, Vec2 initial_velocity, float initial_angular) {
     STEP_MARK(ts);
@@ -682,12 +683,13 @@
             f = car_frame(v, car);
             framed = true;
         }
-        uint32_t made = pair_contacts(w, v, car, f, ci, push, [&](const Contact& c) {
+        pair_contacts(w, v, car, f, ci, push, [&](const Contact& c) {
             STEP_MARK(tm);
             merge_contact(v, car, c);
             STEP_SECTION(11, tm);
         });
-        made_contacts |= made ? 1u << ci : 0u;
+        // Keep cached contacts eligible when SAT overlaps but produces no new point.
+        made_contacts |= 1u << ci;
     }
     STEP_SECTION(2, tc);
     SolveResult r = solve_contacts(w, v, car, made_contacts, k.velocity, k.angular, k.previous_velocity, k.previous_angular);