diff --git a/src/image.c b/src/image.c
index 7284a3d..6300692 100644
--- a/src/image.c
+++ b/src/image.c
@@ -20,8 +20,8 @@
 #include "sha256.h"
 #endif
 
-#define IMAGE_CHUNK_SIZE 124
-#define MACRO_CHUNK_SIZE 302
+#define IMAGE_CHUNK_SIZE 216 // 124 for identical output to newtmgr
+#define MACRO_CHUNK_SIZE 432 // 302 ""
 
 #define CRC16_INITIAL_CRC       0       /* what to seed crc16 with */
 #define CRC_CITT_POLYMINAL 0x1021