diff --git a/akka-testkit/src/test/scala/akka/testkit/TestTimeSpec.scala b/akka-testkit/src/test/scala/akka/testkit/TestTimeSpec.scala
index e12cd51e34..e7642c1c29 100644
--- a/akka-testkit/src/test/scala/akka/testkit/TestTimeSpec.scala
+++ b/akka-testkit/src/test/scala/akka/testkit/TestTimeSpec.scala
@@ -12,13 +12,15 @@ class TestTimeSpec extends AkkaSpec(Map("akka.test.timefactor" -> 2.0)) with Bef
   "A TestKit" must {
 
     "correctly dilate times" taggedAs TimingTest in {
+      1.second.dilated.toNanos must be(1000000000L * testKitSettings.TestTimeFactor)
+
       val probe = TestProbe()
       val now = System.nanoTime
       intercept[AssertionError] { probe.awaitCond(false, Duration("1 second")) }
       val diff = System.nanoTime - now
       val target = (1000000000l * testKitSettings.TestTimeFactor).toLong
-      diff must be > (target - 300000000l)
-      diff must be < (target + 300000000l)
+      diff must be > (target - 500000000l)
+      diff must be < (target + 500000000l)
     }
 
     "awaitAssert must throw correctly" in {