diff --git a/akka-actor-tests/src/test/scala/akka/actor/LocalActorRefProviderSpec.scala b/akka-actor-tests/src/test/scala/akka/actor/LocalActorRefProviderSpec.scala
index 629fb814c4..8b92fd144a 100644
--- a/akka-actor-tests/src/test/scala/akka/actor/LocalActorRefProviderSpec.scala
+++ b/akka-actor-tests/src/test/scala/akka/actor/LocalActorRefProviderSpec.scala
@@ -9,8 +9,21 @@ import akka.util.duration._
 import akka.util.Timeout
 import akka.dispatch.{ Await, Future }
 
+object LocalActorRefProviderSpec {
+  val config = """
+    akka {
+      actor {
+        default-dispatcher {
+          core-pool-size-min = 8
+          core-pool-size-max = 16
+        }
+      }
+    }
+  """
+}
+
 @org.junit.runner.RunWith(classOf[org.scalatest.junit.JUnitRunner])
-class LocalActorRefProviderSpec extends AkkaSpec {
+class LocalActorRefProviderSpec extends AkkaSpec(LocalActorRefProviderSpec.config) {
   "An LocalActorRefProvider" must {
 
     "find actor refs using actorFor" in {
diff --git a/akka-actor-tests/src/test/scala/akka/config/ConfigSpec.scala b/akka-actor-tests/src/test/scala/akka/config/ConfigSpec.scala
index 5c7f2770c8..9b214423c3 100644
--- a/akka-actor-tests/src/test/scala/akka/config/ConfigSpec.scala
+++ b/akka-actor-tests/src/test/scala/akka/config/ConfigSpec.scala
@@ -26,8 +26,8 @@ class ConfigSpec extends AkkaSpec(ConfigFactory.defaultReference) {
       getString("akka.actor.default-dispatcher.type") must equal("Dispatcher")
       getString("akka.actor.default-dispatcher.name") must equal("default-dispatcher")
       getMilliseconds("akka.actor.default-dispatcher.keep-alive-time") must equal(60 * 1000)
-      getDouble("akka.actor.default-dispatcher.core-pool-size-factor") must equal(8.0)
-      getDouble("akka.actor.default-dispatcher.max-pool-size-factor") must equal(8.0)
+      getDouble("akka.actor.default-dispatcher.core-pool-size-factor") must equal(3.0)
+      getDouble("akka.actor.default-dispatcher.max-pool-size-factor") must equal(3.0)
       getInt("akka.actor.default-dispatcher.task-queue-size") must equal(-1)
       getString("akka.actor.default-dispatcher.task-queue-type") must equal("linked")
       getBoolean("akka.actor.default-dispatcher.allow-core-timeout") must equal(true)
diff --git a/akka-actor-tests/src/test/scala/akka/routing/ConfiguredLocalRoutingSpec.scala b/akka-actor-tests/src/test/scala/akka/routing/ConfiguredLocalRoutingSpec.scala
index 032c4da921..f213379d17 100644
--- a/akka-actor-tests/src/test/scala/akka/routing/ConfiguredLocalRoutingSpec.scala
+++ b/akka-actor-tests/src/test/scala/akka/routing/ConfiguredLocalRoutingSpec.scala
@@ -7,8 +7,21 @@ import akka.testkit._
 import akka.util.duration._
 import akka.dispatch.Await
 
+object ConfiguredLocalRoutingSpec {
+  val config = """
+    akka {
+      actor {
+        default-dispatcher {
+          core-pool-size-min = 8
+          core-pool-size-max = 16
+        }
+      }
+    }
+  """
+}
+
 @org.junit.runner.RunWith(classOf[org.scalatest.junit.JUnitRunner])
-class ConfiguredLocalRoutingSpec extends AkkaSpec with DefaultTimeout with ImplicitSender {
+class ConfiguredLocalRoutingSpec extends AkkaSpec(ConfiguredLocalRoutingSpec.config) with DefaultTimeout with ImplicitSender {
 
   val deployer = system.asInstanceOf[ActorSystemImpl].provider.deployer
 
diff --git a/akka-actor/src/main/resources/reference.conf b/akka-actor/src/main/resources/reference.conf
index f6b7188192..efbaff0afc 100644
--- a/akka-actor/src/main/resources/reference.conf
+++ b/akka-actor/src/main/resources/reference.conf
@@ -165,23 +165,23 @@ akka {
       keep-alive-time = 60s
 
       # minimum number of threads to cap factor-based core number to
-      core-pool-size-min = 8
+      core-pool-size-min = 6
 
       # No of core threads ... ceil(available processors * factor)
-      core-pool-size-factor = 8.0
+      core-pool-size-factor = 3.0
 
       # maximum number of threads to cap factor-based number to
-      core-pool-size-max = 4096
+      core-pool-size-max = 64
 
       # Hint: max-pool-size is only used for bounded task queues
       # minimum number of threads to cap factor-based max number to
-      max-pool-size-min = 8
+      max-pool-size-min = 6
 
       # Max no of threads ... ceil(available processors * factor)
-      max-pool-size-factor  = 8.0
+      max-pool-size-factor  = 3.0
 
       # maximum number of threads to cap factor-based max number to
-      max-pool-size-max = 4096
+      max-pool-size-max = 64
 
       # Specifies the bounded capacity of the task queue (< 1 == unbounded)
       task-queue-size = -1
diff --git a/akka-transactor/src/test/scala/akka/transactor/CoordinatedIncrementSpec.scala b/akka-transactor/src/test/scala/akka/transactor/CoordinatedIncrementSpec.scala
index 47067d3595..c6e129f89b 100644
--- a/akka-transactor/src/test/scala/akka/transactor/CoordinatedIncrementSpec.scala
+++ b/akka-transactor/src/test/scala/akka/transactor/CoordinatedIncrementSpec.scala
@@ -14,6 +14,18 @@ import akka.testkit._
 import scala.concurrent.stm._
 
 object CoordinatedIncrement {
+
+  val config = """
+    akka {
+      actor {
+        default-dispatcher {
+          core-pool-size-min = 5
+          core-pool-size-max = 16
+        }
+      }
+    }
+  """
+
   case class Increment(friends: Seq[ActorRef])
   case object GetCount
 
@@ -49,7 +61,7 @@ object CoordinatedIncrement {
 }
 
 @org.junit.runner.RunWith(classOf[org.scalatest.junit.JUnitRunner])
-class CoordinatedIncrementSpec extends AkkaSpec with BeforeAndAfterAll {
+class CoordinatedIncrementSpec extends AkkaSpec(CoordinatedIncrement.config) with BeforeAndAfterAll {
   import CoordinatedIncrement._
 
   implicit val timeout = Timeout(5.seconds.dilated)