diff --git a/src/gt4py/next/program_processors/runners/dace/transformations/auto_optimize.py b/src/gt4py/next/program_processors/runners/dace/transformations/auto_optimize.py
index 799e8ad228..62b658f839 100644
--- a/src/gt4py/next/program_processors/runners/dace/transformations/auto_optimize.py
+++ b/src/gt4py/next/program_processors/runners/dace/transformations/auto_optimize.py
@@ -113,8 +113,8 @@ def gt_auto_optimize(
     gpu: bool,
     unit_strides_kind: Optional[gtx_common.DimensionKind] = None,
     make_persistent: bool = False,
-    gpu_block_size: Optional[Sequence[int | str] | str] = (32, 8, 1),
-    gpu_block_size_1d: Optional[Sequence[int | str] | str] = (64, 1, 1),
+    gpu_block_size: Optional[Sequence[int | str] | str] = (256, 1, 1),
+    gpu_block_size_1d: Optional[Sequence[int | str] | str] = None,
     gpu_block_size_2d: Optional[Sequence[int | str] | str] = None,
     gpu_block_size_3d: Optional[Sequence[int | str] | str] = None,
     gpu_maxnreg: Optional[int] = None,