diff --git a/book/src/builders.md b/book/src/builders.md
index b7bf877d04c..930d330d994 100644
--- a/book/src/builders.md
+++ b/book/src/builders.md
@@ -157,7 +157,7 @@ You can also directly configure these fields in the `validator_definitions.yml`
   suggested_fee_recipient: "0x6cc8dcbca744a6e4ffedb98e1d0df903b10abd21"
   gas_limit: 30000001
   builder_proposals: true
-  builder_boost_factor: 80
+  builder_boost_factor: 50
 - enabled: false
   voting_public_key: "0xa5566f9ec3c6e1fdf362634ebec9ef7aceb0e460e5079714808388e5d48f4ae1e12897fed1bea951c17fa389d511e477"
   type: local_keystore voting_keystore_path: /home/paul/.lighthouse/validators/0xa5566f9ec3c6e1fdf362634ebec9ef7aceb0e460e5079714808388e5d48f4ae1e12897fed1bea951c17fa389d511e477/voting-keystore.json