diff --git a/read.c b/read.c
index a496148..3555430 100644
--- a/read.c
+++ b/read.c
@@ -60,7 +60,7 @@ static void tar_write_last(void);
 #pragma mark DECLARE READ BUFFER
 
 #define STREAMSIZE (1024 * 1024)
-#define MAXSPLITSIZE (64 * 1024 * 1024) // xz -9 blocksize
+#define MAXSPLITSIZE ((64 * 1024 * 1024) * 2) // xz -9 blocksize * 2
 
 static pipeline_item_t *gRbufPI = NULL;
 static io_block_t *gRbuf = NULL;
diff --git a/write.c b/write.c
index 71ffe64..f88a811 100644
--- a/write.c
+++ b/write.c
@@ -16,7 +16,7 @@ struct io_block_t {
 
 #pragma mark GLOBALS
 
-double gBlockFraction = 1.0;
+double gBlockFraction = 2.0;
 
 static bool gTar = true;