diff --git a/src/machi_chain_manager1.erl b/src/machi_chain_manager1.erl
index a983ea7..e784b00 100644
--- a/src/machi_chain_manager1.erl
+++ b/src/machi_chain_manager1.erl
@@ -171,7 +171,7 @@ init({MyName, InitMembersDict, MgrOpts}) ->
     All_list = [P#p_srvr.name || {_, P} <- orddict:to_list(MembersDict)],
     Opt = fun(Key, Default) -> proplists:get_value(Key, MgrOpts, Default) end,
     RunEnv = [{seed, Opt(seed, now())},
-              {use_partition_simulator, Opt(use_partition_simulator, true)},
+              {use_partition_simulator, Opt(use_partition_simulator, false)},
               {network_partitions, Opt(network_partitions, [])},
               {network_islands, Opt(network_islands, [])},
               {flapping_i, Opt(flapping, [])},
diff --git a/test/machi_chain_manager1_converge_demo.erl b/test/machi_chain_manager1_converge_demo.erl
index 30e7b23..af14870 100644
--- a/test/machi_chain_manager1_converge_demo.erl
+++ b/test/machi_chain_manager1_converge_demo.erl
@@ -167,7 +167,8 @@ convergence_demo_testfun(NumFLUs) ->
                  {Name, PPid}
              end || {#p_srvr{name=Name}=P, _Dir} <- PsDirs],
     MembersDict = machi_projection:make_members_dict(Ps),
-    MgrOpts = [private_write_verbose, {active_mode,false}],
+    MgrOpts = [private_write_verbose, {active_mode,false},
+              {use_partition_simulator, true}],
     MgrNamez =
         [begin
              {ok, MPid} = ?MGR:start_link(P#p_srvr.name, MembersDict, MgrOpts),