diff --git a/tests/bbr_integration/test_bbr_integration.c b/tests/bbr_integration/test_bbr_integration.c
index f0a64dea..35edf070 100644
--- a/tests/bbr_integration/test_bbr_integration.c
+++ b/tests/bbr_integration/test_bbr_integration.c
@@ -53,7 +53,7 @@
 #define EMU_QUEUE_PKTS   65     /* ~100KB at MTU 1400-1600 */
 
 /* Convert raw BBR bandwidth (BW_UNIT * bytes / usec) to kbps */
-#define BW_RAW_TO_KBPS(bw) ((double)(bw) / 2097.152)
+#define BW_RAW_TO_KBPS(bw) ((double)(bw) * 8000.0 / BW_UNIT)
 
 /* ===== BBR name helpers ===== */
 static const char* bbr_mode_name(uint8_t m) {
diff --git a/tests/test_etcp_bbr.c b/tests/test_etcp_bbr.c
index 91b09337..df3f4054 100644
--- a/tests/test_etcp_bbr.c
+++ b/tests/test_etcp_bbr.c
@@ -55,6 +55,24 @@ static int test_byte_rate(void) {
     PASS(); return 0;
 }
 
+/* Байтовый Q16 сохраняет многогигабитные скорости; выход uint32 насыщается, а не оборачивается. */
+static int test_large_rate(void) {
+    MSEG("multi-gigabit rate and pacing saturation");
+    const uint32_t intervals[] = {5, 1}, expected[] = {1980000000, UINT32_MAX};
+    for (unsigned i = 0; i < 2; i++) {
+        struct bbr s = { .now_tb = 10000 }; bbr_init(&s);
+        s.mode = BBR_PROBE_BW; s.full_bw_reached = 1; s.cycle_idx = BBR_BW_PROBE_CRUISE;
+        s.cycle_mstamp_tb = s.now_tb; s.probe_wait_us = 2000000;
+        uint32_t cwnd = 100000, pacing = 0;
+        struct bbr_rate_sample rs = { .delivered = 10000, .interval_us = intervals[i], .rtt_us = 20000,
+            .acked_sacked = 1000, .tx_in_flight = 40000 };
+        bbr_main(&s, &rs, &cwnd, &pacing, 1400, 40000, 0);
+        DEBUG_INFO(DEBUG_CATEGORY_DEBUG, "BBR high rate: interval_us=%u pacing=%u expected=%u", intervals[i], pacing, expected[i]);
+        if (pacing != expected[i]) FAIL("high rate was truncated or wrapped");
+    }
+    PASS(); return 0;
+}
+
 static int test_init(void)
 {
     MSEG("bbr_init — startup mode");
@@ -77,8 +95,8 @@ static int test_startup_growth(void)
     s.init_cwnd = 4; g_cwnd = 5600; g_pacing = 0;
     uint32_t prev = g_cwnd;
     for (int r = 0; r < 4; r++) {
-        s.now_tb += 10000;
-        for (int a = 0; a < 5; a++) run_ack(&s, 1400, 10000, 0, 0, prev);
+        // Подтверждаем целое окно за RTT: доступная полоса растёт вместе с окном, STARTUP должен её освоить.
+        run_ack(&s, prev, 10000, 0, 0, prev);
         if (g_cwnd <= prev) FAIL("cwnd did not grow");
         prev = g_cwnd;
     }
@@ -100,7 +118,6 @@ static int test_full_bw(void)
    // Mode transitions STARTUP→DRAIN→PROBE_BW might all happen in one ACK
     if (s.mode != BBR_DRAIN && s.mode != BBR_PROBE_BW) FAIL("mode not DRAIN/PROBE_BW after full_bw");
     PASS(); return 0;
-    PASS(); return 0;
 }
 
 static int test_loss_startup(void)
@@ -171,6 +188,7 @@ int main(void)
 {
     debug_config_init(); debug_set_level(DEBUG_LEVEL_ERROR); debug_set_category_level(DEBUG_CATEGORY_DEBUG, DEBUG_LEVEL_INFO);
     test_byte_rate();
+    test_large_rate();
     test_init();
     test_startup_growth();
     test_full_bw();