diff --git a/zebra-test/src/mock_service.rs b/zebra-test/src/mock_service.rs
index e919a36d..ef1dc412 100644
--- a/zebra-test/src/mock_service.rs
+++ b/zebra-test/src/mock_service.rs
@@ -77,8 +77,9 @@ const DEFAULT_PROXY_CHANNEL_SIZE: usize = 100;
 /// Note that if a test checks that no requests are received, each check has to wait for this
 /// amount of time, so this may affect the test execution time.
 ///
-/// We've seen delays up to 67ms on busy Linux and macOS machines.
-pub const DEFAULT_MAX_REQUEST_DELAY: Duration = Duration::from_millis(150);
+/// We've seen delays up to 67ms on busy Linux and macOS machines,
+/// and some other timeout failures even with a 150ms timeout.
+pub const DEFAULT_MAX_REQUEST_DELAY: Duration = Duration::from_millis(300);
 
 /// An internal type representing the item that's sent in the [`broadcast`] channel.
 ///
diff --git a/zebrad/src/components/sync/recent_sync_lengths.rs b/zebrad/src/components/sync/recent_sync_lengths.rs
index acf32f07..ca2fd589 100644
--- a/zebrad/src/components/sync/recent_sync_lengths.rs
+++ b/zebrad/src/components/sync/recent_sync_lengths.rs
@@ -31,7 +31,7 @@ impl RecentSyncLengths {
     /// * clearing temporary errors and temporary syncs quickly
     /// * distinguishing between temporary and sustained syncs/errors
     /// * activating the syncer shortly after reaching the chain tip
-    pub const MAX_RECENT_LENGTHS: usize = 2;
+    pub const MAX_RECENT_LENGTHS: usize = 3;
 
     /// Create a new instance of [`RecentSyncLengths`]
     /// and a [`watch::Receiver`] endpoint for receiving recent sync lengths.