diff --git a/config/rv32gc/imperas.ic b/config/rv32gc/imperas.ic
index 46d0d31c3..2ba3c1280 100644
--- a/config/rv32gc/imperas.ic
+++ b/config/rv32gc/imperas.ic
@@ -36,7 +36,7 @@
 --override cpu/Zicboz=T
 --override cmomp_bytes=64  # Zic64b
 --override cmoz_bytes=64   # Zic64b
---override lr_sc_grain=8   # Za64rs requires <=64; we use native word size
+--override lr_sc_grain=4   # Za64rs requires <=64; we use native word size
 
 # 64 KiB continuous huge pages supported
 #--override cpu/Svpbmt=F