diff --git a/lib/ultrajson.h b/lib/ultrajson.h
index 79abf1d..05e62a9 100644
--- a/lib/ultrajson.h
+++ b/lib/ultrajson.h
@@ -336,7 +336,7 @@ typedef struct __JSONObjectDecoder
 EXPORTFUNCTION JSOBJ JSON_DecodeObject(JSONObjectDecoder *dec, const char *buffer, size_t cbBuffer);
 
 #define DCONV_DECIMAL_IN_SHORTEST_LOW -6
-#define DCONV_DECIMAL_IN_SHORTEST_HIGH 21
+#define DCONV_DECIMAL_IN_SHORTEST_HIGH 16
 
 enum dconv_d2s_flags {
   DCONV_D2S_NO_FLAGS = 0,
diff --git a/python/objToJSON.c b/python/objToJSON.c
index 7b11d57..b6ceff2 100644
--- a/python/objToJSON.c
+++ b/python/objToJSON.c
@@ -827,7 +827,7 @@ PyObject* objToJSON(PyObject* self, PyObject *args, PyObject *kwargs)
   }
 
 
-  dconv_d2s_init(DCONV_D2S_EMIT_TRAILING_DECIMAL_POINT | DCONV_D2S_EMIT_TRAILING_ZERO_AFTER_POINT,
+  dconv_d2s_init(DCONV_D2S_EMIT_TRAILING_DECIMAL_POINT | DCONV_D2S_EMIT_TRAILING_ZERO_AFTER_POINT | DCONV_D2S_EMIT_POSITIVE_EXPONENT_SIGN,
                  csInf, csNan, 'e', DCONV_DECIMAL_IN_SHORTEST_LOW, DCONV_DECIMAL_IN_SHORTEST_HIGH, 0, 0);
 
   PRINTMARK();
diff --git a/tests/test_ujson.py b/tests/test_ujson.py
index b11e5d2..ea8a17f 100644
--- a/tests/test_ujson.py
+++ b/tests/test_ujson.py
@@ -78,6 +78,11 @@ def test_double_long_decimal_issue():
     assert sut == decoded
 
 
+@pytest.mark.parametrize("val", [1e10, 1e15, 1e16, 1e20])
+def test_encode_float_string_rep(val):
+    assert ujson.dumps(val) == json.dumps(val)
+
+
 def test_encode_decode_long_decimal():
     sut = {"a": -528656961.4399388}
     encoded = ujson.dumps(sut)