diff --git a/install/scripts/start-bn.sh b/install/scripts/start-bn.sh
index cd13a2d7..bba0f2ef 100755
--- a/install/scripts/start-bn.sh
+++ b/install/scripts/start-bn.sh
@@ -237,7 +237,8 @@ if [ "$CC_CLIENT" = "prysm" ]; then
         --grpc-gateway-port ${BN_API_PORT:-5052} \
         --eth1-header-req-limit 150 \
         --jwt-secret=/secrets/jwtsecret \
-        --api-timeout 600 \
+        --api-timeout 20s \
+        --enable-experimental-backfill \
         $BN_ADDITIONAL_FLAGS"
 
     if [ ! -z "$MEV_BOOST_URL" ]; then
diff --git a/install/scripts/start-vc.sh b/install/scripts/start-vc.sh
index cf6da034..c9cb779a 100755
--- a/install/scripts/start-vc.sh
+++ b/install/scripts/start-vc.sh
@@ -66,7 +66,7 @@ if [ "$CC_CLIENT" = "lighthouse" ]; then
     fi
 
     if [ "$ENABLE_MEV_BOOST" = "true" ]; then
-        CMD="$CMD --builder-proposals"
+        CMD="$CMD --builder-proposals --prefer-builder-proposals"
     fi
 
     if [ "$ENABLE_METRICS" = "true" ]; then