diff --git a/miner/minerconfig/config.go b/miner/minerconfig/config.go
index 7873702bf2..fc13440b30 100644
--- a/miner/minerconfig/config.go
+++ b/miner/minerconfig/config.go
@@ -32,11 +32,12 @@ var (
 	defaultRecommit              = 10 * time.Second
 	defaultMaxWaitProposalInSecs = uint64(45)
 
-	defaultDelayLeftOver         = 20 * time.Millisecond
+	// Extra time for finalizing and committing blocks (excludes writing to disk).
+	defaultDelayLeftOver         = 25 * time.Millisecond
 	defaultBidSimulationLeftOver = 30 * time.Millisecond
-	// Bid simulation speed on mainnet ranges from 400 to 700 mgasps.
-	// Here we assume 500 for estimation.
-	defaultNoInterruptLeftOver = 170 * time.Millisecond // For gas limit 75M
+	// For estimation, assume 500 Mgas/s:
+	//	(100M gas / 500 Mgas/s) * 1000 ms + 10 ms buffer + defaultDelayLeftOver ≈ 235 ms.
+	defaultNoInterruptLeftOver = 235 * time.Millisecond
 )
 
 // Other default MEV-related configurations
@@ -66,7 +67,7 @@ type Config struct {
 
 // DefaultConfig contains default settings for miner.
 var DefaultConfig = Config{
-	GasCeil:  75000000,
+	GasCeil:  100000000,
 	GasPrice: big.NewInt(params.GWei),
 
 	// The default recommit time is chosen as two seconds since
diff --git a/tests/truffle/config/config-validator.toml b/tests/truffle/config/config-validator.toml
index b36bfa8330..a3844284c4 100644
--- a/tests/truffle/config/config-validator.toml
+++ b/tests/truffle/config/config-validator.toml
@@ -11,7 +11,7 @@ TrieTimeout = 6000000000
 EnablePreimageRecording = false
 
 [Eth.Miner]
-GasCeil = 75000000
+GasCeil = 100000000
 GasPrice = 100000000
 
 [Eth.GPO]