diff --git a/sequencer/src/api.rs b/sequencer/src/api.rs
index dee017a6fa..d035419609 100644
--- a/sequencer/src/api.rs
+++ b/sequencer/src/api.rs
@@ -554,6 +554,7 @@ pub mod test_helpers {
         api_config: Options,
     }
 
+    #[derive(Clone)]
     pub struct TestNetworkConfigBuilder<const NUM_NODES: usize, P, C>
     where
         P: PersistenceOptions,
@@ -592,6 +593,19 @@ pub mod test_helpers {
                 api_config: None,
             }
         }
+
+        pub fn with_max_block_size(&self, max_block_size: u64) -> Self {
+            let cf = ChainConfig {
+                max_block_size: max_block_size.into(),
+                ..Default::default()
+            }
+            .into();
+
+            let mut cfg = self.clone();
+            cfg.state.iter_mut().for_each(|s| s.chain_config = cf);
+
+            cfg
+        }
     }
 
     impl<const NUM_NODES: usize, P, C> TestNetworkConfigBuilder<{ NUM_NODES }, P, C>
diff --git a/sequencer/src/bin/espresso-dev-node.rs b/sequencer/src/bin/espresso-dev-node.rs
index dcd4adb588..24e0e4aab3 100644
--- a/sequencer/src/bin/espresso-dev-node.rs
+++ b/sequencer/src/bin/espresso-dev-node.rs
@@ -145,6 +145,15 @@ struct Args {
     #[clap(short, long, env = "ESPRESSO_DEV_NODE_PORT", default_value = "20000")]
     dev_node_port: u16,
 
+    /// Port for connecting to the builder.
+    #[clap(
+        short,
+        long,
+        env = "ESPRESSO_DEV_NODE_MAX_BLOCK_SIZE",
+        default_value = "1000000"
+    )]
+    max_block_size: u64,
+
     #[clap(flatten)]
     sql: persistence::sql::Options,
 
@@ -177,6 +186,7 @@ async fn main() -> anyhow::Result<()> {
         alt_prover_retry_intervals,
         alt_prover_update_intervals,
         l1_interval,
+        max_block_size,
     } = cli_params;
 
     logging.init();
@@ -215,6 +225,7 @@ async fn main() -> anyhow::Result<()> {
     let config = TestNetworkConfigBuilder::<NUM_NODES, _, _>::with_num_nodes()
         .api_config(api_options)
         .network_config(network_config)
+        .with_max_block_size(max_block_size)
         .build();
 
     let network =
@@ -620,6 +631,7 @@ mod tests {
                 tmp_dir.path().as_os_str(),
             )
             .env("ESPRESSO_SEQUENCER_DATABASE_MAX_CONNECTIONS", "25")
+            .env("ESPRESSO_DEV_NODE_MAX_BLOCK_SIZE", "500000")
             .spawn()
             .unwrap();
 
@@ -709,7 +721,7 @@ mod tests {
 
         {
             // transactions with size larger than max_block_size result in an error
-            let extremely_large_tx = Transaction::new(100_u32.into(), vec![0; 50120]);
+            let extremely_large_tx = Transaction::new(100_u32.into(), vec![0; 7 * 1000 * 1000]);
             api_client
                 .post::<Commitment<Transaction>>("submit/submit")
                 .body_json(&extremely_large_tx)