diff --git a/cmd/activator/main.go b/cmd/activator/main.go
index 69e80f03682a..891a375a9553 100644
--- a/cmd/activator/main.go
+++ b/cmd/activator/main.go
@@ -143,11 +143,6 @@ func (a *activationHandler) handler(w http.ResponseWriter, r *http.Request) {
 	proxy.Transport = retryRoundTripper{
 		logger: a.logger,
 	}
-
-	// TODO: Clear the host to avoid 404's.
-	// https://github.com/knative/serving/issues/964
-	r.Host = ""
-
 	proxy.ServeHTTP(w, r)
 }
 
diff --git a/pkg/controller/route/resources/virtual_service.go b/pkg/controller/route/resources/virtual_service.go
index 937027b216dc..7724602de805 100644
--- a/pkg/controller/route/resources/virtual_service.go
+++ b/pkg/controller/route/resources/virtual_service.go
@@ -35,19 +35,6 @@ const (
 	PortNumber = 80
 	PortName   = "http"
 
-	// There is a bug in Istio 0.8 preventing the timeout to
-	// be set more than 15 seconds.  The bug is now fixed at HEAD,
-	// but not yet released.  15 seconds is too short for our 0->1
-	// use case (see https://github.com/knative/serving/issues/1297).
-	//
-	// HACK: This applies the workaround suggested in
-	//     https://github.com/istio/istio/issues/6230
-	// to allow setting a longer timeout than 15s.
-	//
-	// TODO: Remove hack when Istio 1.0 is out.
-	IstioTimeoutHackHeaderKey   = "x-envoy-upstream-rq-timeout-ms"
-	IstioTimeoutHackHeaderValue = "0"
-
 	DefaultRouteTimeout = "60s"
 )
 
@@ -143,9 +130,6 @@ func makeVirtualServiceRoute(domains []string, ns string, targets []traffic.Revi
 		Match:   matches,
 		Route:   weights,
 		Timeout: DefaultRouteTimeout,
-		AppendHeaders: map[string]string{
-			IstioTimeoutHackHeaderKey: IstioTimeoutHackHeaderValue,
-		},
 	}
 	// Add traffic rules for activator.
 	return addActivatorRoutes(&route, ns, inactive)
@@ -193,8 +177,10 @@ func addActivatorRoutes(r *v1alpha3.HTTPRoute, ns string, inactive []traffic.Rev
 		},
 		Weight: totalInactivePercent,
 	})
-	r.AppendHeaders[controller.GetRevisionHeaderName()] = maxInactiveTarget.RevisionName
-	r.AppendHeaders[controller.GetRevisionHeaderNamespace()] = ns
+	r.AppendHeaders = map[string]string{
+		controller.GetRevisionHeaderName():      maxInactiveTarget.RevisionName,
+		controller.GetRevisionHeaderNamespace(): ns,
+	}
 	return r
 }
 
diff --git a/pkg/controller/route/resources/virtual_service_test.go b/pkg/controller/route/resources/virtual_service_test.go
index 5cc0f5651233..9f148bbdab0d 100644
--- a/pkg/controller/route/resources/virtual_service_test.go
+++ b/pkg/controller/route/resources/virtual_service_test.go
@@ -123,9 +123,6 @@ func TestMakeVirtualServiceSpec_CorrectRoutes(t *testing.T) {
 			Weight: 100,
 		}},
 		Timeout: DefaultRouteTimeout,
-		AppendHeaders: map[string]string{
-			IstioTimeoutHackHeaderKey: IstioTimeoutHackHeaderValue,
-		},
 	}, {
 		Match: []v1alpha3.HTTPMatchRequest{{
 			Authority: &v1alpha3.StringMatch{Exact: "v1.domain.com"},
@@ -138,9 +135,6 @@ func TestMakeVirtualServiceSpec_CorrectRoutes(t *testing.T) {
 			Weight: 100,
 		}},
 		Timeout: DefaultRouteTimeout,
-		AppendHeaders: map[string]string{
-			IstioTimeoutHackHeaderKey: IstioTimeoutHackHeaderValue,
-		},
 	}}
 	routes := MakeVirtualService(r, &traffic.TrafficConfig{Targets: targets}).Spec.Http
 	if diff := cmp.Diff(expected, routes); diff != "" {
@@ -214,9 +208,6 @@ func TestMakeVirtualServiceRoute_Vanilla(t *testing.T) {
 			Weight: 100,
 		}},
 		Timeout: DefaultRouteTimeout,
-		AppendHeaders: map[string]string{
-			IstioTimeoutHackHeaderKey: IstioTimeoutHackHeaderValue,
-		},
 	}
 	if diff := cmp.Diff(&expected, route); diff != "" {
 		t.Errorf("Unexpected route  (-want +got): %v", diff)
@@ -254,9 +245,6 @@ func TestMakeVirtualServiceRoute_ZeroPercentTarget(t *testing.T) {
 			Weight: 100,
 		}},
 		Timeout: DefaultRouteTimeout,
-		AppendHeaders: map[string]string{
-			IstioTimeoutHackHeaderKey: IstioTimeoutHackHeaderValue,
-		},
 	}
 	if diff := cmp.Diff(&expected, route); diff != "" {
 		t.Errorf("Unexpected route  (-want +got): %v", diff)
@@ -301,9 +289,6 @@ func TestMakeVirtualServiceRoute_TwoTargets(t *testing.T) {
 			Weight: 10,
 		}},
 		Timeout: DefaultRouteTimeout,
-		AppendHeaders: map[string]string{
-			IstioTimeoutHackHeaderKey: IstioTimeoutHackHeaderValue,
-		},
 	}
 	if diff := cmp.Diff(&expected, route); diff != "" {
 		t.Errorf("Unexpected route  (-want +got): %v", diff)
@@ -339,7 +324,6 @@ func TestMakeVirtualServiceRoute_VanillaScaledToZero(t *testing.T) {
 		AppendHeaders: map[string]string{
 			"knative-serving-revision":  "revision",
 			"knative-serving-namespace": "test-ns",
-			IstioTimeoutHackHeaderKey:   IstioTimeoutHackHeaderValue,
 		},
 		Timeout: DefaultRouteTimeout,
 	}
@@ -382,7 +366,6 @@ func TestMakeVirtualServiceRoute_TwoInactiveTargets(t *testing.T) {
 		AppendHeaders: map[string]string{
 			"knative-serving-revision":  "revision",
 			"knative-serving-namespace": "test-ns",
-			IstioTimeoutHackHeaderKey:   IstioTimeoutHackHeaderValue,
 		},
 		Timeout: DefaultRouteTimeout,
 	}
@@ -423,9 +406,6 @@ func TestMakeVirtualServiceRoute_ZeroPercentNamedTargetScaledToZero(t *testing.T
 			Weight: 100,
 		}},
 		Timeout: DefaultRouteTimeout,
-		AppendHeaders: map[string]string{
-			IstioTimeoutHackHeaderKey: IstioTimeoutHackHeaderValue,
-		},
 	}
 	if diff := cmp.Diff(&expected, route); diff != "" {
 		t.Errorf("Unexpected route  (-want +got): %v", diff)
diff --git a/pkg/controller/route/route_test.go b/pkg/controller/route/route_test.go
index 0079e3b44890..d34bab42a4f1 100644
--- a/pkg/controller/route/route_test.go
+++ b/pkg/controller/route/route_test.go
@@ -315,9 +315,8 @@ func TestCreateRouteForOneReserveRevision(t *testing.T) {
 			}},
 			Route: []v1alpha3.DestinationWeight{getActivatorDestinationWeight(100)},
 			AppendHeaders: map[string]string{
-				ctrl.GetRevisionHeaderName():        "test-rev",
-				ctrl.GetRevisionHeaderNamespace():   testNamespace,
-				resources.IstioTimeoutHackHeaderKey: resources.IstioTimeoutHackHeaderValue,
+				ctrl.GetRevisionHeaderName():      "test-rev",
+				ctrl.GetRevisionHeaderNamespace(): testNamespace,
 			},
 			Timeout: resources.DefaultRouteTimeout,
 		}},
@@ -407,9 +406,6 @@ func TestCreateRouteWithMultipleTargets(t *testing.T) {
 				Weight: 10,
 			}},
 			Timeout: resources.DefaultRouteTimeout,
-			AppendHeaders: map[string]string{
-				resources.IstioTimeoutHackHeaderKey: resources.IstioTimeoutHackHeaderValue,
-			},
 		}},
 	}
 	if diff := cmp.Diff(expectedSpec, vs.Spec); diff != "" {
@@ -493,9 +489,8 @@ func TestCreateRouteWithOneTargetReserve(t *testing.T) {
 				Weight: 90,
 			}, getActivatorDestinationWeight(10)},
 			AppendHeaders: map[string]string{
-				ctrl.GetRevisionHeaderName():        "test-rev",
-				ctrl.GetRevisionHeaderNamespace():   testNamespace,
-				resources.IstioTimeoutHackHeaderKey: resources.IstioTimeoutHackHeaderValue,
+				ctrl.GetRevisionHeaderName():      "test-rev",
+				ctrl.GetRevisionHeaderNamespace(): testNamespace,
 			},
 			Timeout: resources.DefaultRouteTimeout,
 		}},
@@ -600,9 +595,6 @@ func TestCreateRouteWithDuplicateTargets(t *testing.T) {
 				Weight: 50,
 			}},
 			Timeout: resources.DefaultRouteTimeout,
-			AppendHeaders: map[string]string{
-				resources.IstioTimeoutHackHeaderKey: resources.IstioTimeoutHackHeaderValue,
-			},
 		}, {
 			Match: []v1alpha3.HTTPMatchRequest{{Authority: &v1alpha3.StringMatch{Exact: "test-revision-1." + domain}}},
 			Route: []v1alpha3.DestinationWeight{{
@@ -613,9 +605,6 @@ func TestCreateRouteWithDuplicateTargets(t *testing.T) {
 				Weight: 100,
 			}},
 			Timeout: resources.DefaultRouteTimeout,
-			AppendHeaders: map[string]string{
-				resources.IstioTimeoutHackHeaderKey: resources.IstioTimeoutHackHeaderValue,
-			},
 		}, {
 			Match: []v1alpha3.HTTPMatchRequest{{Authority: &v1alpha3.StringMatch{Exact: "test-revision-2." + domain}}},
 			Route: []v1alpha3.DestinationWeight{{
@@ -626,9 +615,6 @@ func TestCreateRouteWithDuplicateTargets(t *testing.T) {
 				Weight: 100,
 			}},
 			Timeout: resources.DefaultRouteTimeout,
-			AppendHeaders: map[string]string{
-				resources.IstioTimeoutHackHeaderKey: resources.IstioTimeoutHackHeaderValue,
-			},
 		}},
 	}
 	if diff := cmp.Diff(expectedSpec, vs.Spec); diff != "" {
@@ -716,9 +702,6 @@ func TestCreateRouteWithNamedTargets(t *testing.T) {
 				Weight: 50,
 			}},
 			Timeout: resources.DefaultRouteTimeout,
-			AppendHeaders: map[string]string{
-				resources.IstioTimeoutHackHeaderKey: resources.IstioTimeoutHackHeaderValue,
-			},
 		}, {
 			Match: []v1alpha3.HTTPMatchRequest{{Authority: &v1alpha3.StringMatch{Exact: "bar." + domain}}},
 			Route: []v1alpha3.DestinationWeight{{
@@ -729,9 +712,6 @@ func TestCreateRouteWithNamedTargets(t *testing.T) {
 				Weight: 100,
 			}},
 			Timeout: resources.DefaultRouteTimeout,
-			AppendHeaders: map[string]string{
-				resources.IstioTimeoutHackHeaderKey: resources.IstioTimeoutHackHeaderValue,
-			},
 		}, {
 			Match: []v1alpha3.HTTPMatchRequest{{Authority: &v1alpha3.StringMatch{Exact: "foo." + domain}}},
 			Route: []v1alpha3.DestinationWeight{{
@@ -742,9 +722,6 @@ func TestCreateRouteWithNamedTargets(t *testing.T) {
 				Weight: 100,
 			}},
 			Timeout: resources.DefaultRouteTimeout,
-			AppendHeaders: map[string]string{
-				resources.IstioTimeoutHackHeaderKey: resources.IstioTimeoutHackHeaderValue,
-			},
 		}},
 	}
 	if diff := cmp.Diff(expectedSpec, vs.Spec); diff != "" {