diff --git a/mandel-core.s b/mandel-core.s
index 5e56e87..a153ff5 100644
--- a/mandel-core.s
+++ b/mandel-core.s
@@ -435,11 +435,13 @@ input_max:
     add 4, dest, arg1, arg2
 .endmacro
 
-; 8 cycles
+; 2-7 cycles
 .macro add_carry dest
-    lda dest ; 3 cyc
-    adc #0   ; 2 cyc
-    sta dest ; 3 cyc
+    .scope
+        bcc after ; 2 cyc
+        inc dest  ; 5 cyc
+    after:
+    .endscope
 .endmacro
 
 ; 2 + 9 * byte cycles
@@ -771,10 +773,10 @@ inner_loop:
 
 .endproc
 
-; min base mem: 81 * 4 + 28 * 2 + 10 + 6 = 396 cyc
-; max base mem: 92 * 4 + 28 * 2 + 50 + 6 = 480 cyc
-; min ext-mem: 51 * 4 + 28 * 2 + 10 + 6 = 276 cyc
-; max ext-mem: 70 * 4 + 28 * 2 + 50 + 6 = 392 cyc
+; min base mem: 81 * 4 + 22 * 2 + 10 + 6 = 384 cyc
+; max base mem: 92 * 4 + 27 * 2 + 50 + 6 = 478 cyc
+; min ext-mem: 51 * 4 + 22 * 2 + 10 + 6 = 264 cyc
+; max ext-mem: 70 * 4 + 27 * 2 + 50 + 6 = 390 cyc
 .macro imul16_impl xe
     .local arg1
     .local arg2
@@ -798,11 +800,11 @@ inner_loop:
 
     imul8 inter, arg1 + 1, arg2, xe     ; 81-92 or 51-70
     add16 result + 1, result + 1, inter ; 20 cyc
-    add_carry result + 3                ; 8 cyc
+    add_carry result + 3                ; 2-7 cyc
 
     imul8 inter, arg1, arg2 + 1, xe     ; 81-92 or 51-70
     add16 result + 1, result + 1, inter ; 20 cyc
-    add_carry result + 3                ; 8 cyc
+    add_carry result + 3                ; 2-7 cyc
 
     ; In case of negative inputs, adjust high word
     ; https://stackoverflow.com/a/28827013
@@ -819,10 +821,10 @@ arg2_pos:
     rts ; 6 cyc
 .endmacro
 
-; min base ram: 5 + 19 * 2 + 81 + 28 * 2 + 6 = 186
-; max base ram: 23 + 19 * 2 + 92 + 28 * 2 + 6 = 215
-; min ext ram: 5 + 19 * 2 + 51 + 28 * 2 + 6 = 156
-; max ext ram: 23 + 19 * 2 + 70 + 28 * 2 + 6 = 193
+; min base ram: 5 + 19 * 2 + 81 + 22 * 2 + 6 = 174
+; max base ram: 23 + 19 * 2 + 92 + 27 * 2 + 6 = 213
+; min ext ram: 5 + 19 * 2 + 51 + 22 * 2 + 6 = 144
+; max ext ram: 23 + 19 * 2 + 70 + 27 * 2 + 6 = 191
 .macro sqr16_impl xe
     .scope
         arg = FR0    ; 16-bit arg (clobbered)
@@ -847,9 +849,9 @@ arg2_pos:
 
         imul8 inter, arg + 1, arg, xe        ; 81-92 / 51-70 cyc
         add16 result + 1, result + 1, inter  ; 20 cyc
-        add_carry result + 3                 ; 8 cyc
+        add_carry result + 3                 ; 2-7 cyc
         add16 result + 1, result + 1, inter  ; 20 cyc
-        add_carry result + 3                 ; 8 cyc
+        add_carry result + 3                 ; 2-7 cyc
 
         rts ; 6 cyc
     .endscope