diff --git a/src/currency_core/currency_format_utils_transactions.cpp b/src/currency_core/currency_format_utils_transactions.cpp
index ffb6d813..0c552fa1 100644
--- a/src/currency_core/currency_format_utils_transactions.cpp
+++ b/src/currency_core/currency_format_utils_transactions.cpp
@@ -215,12 +215,35 @@ namespace currency
     return total;
   }
   //---------------------------------------------------------------
+  inline size_t get_input_expected_signature_size_local(const txin_v& tx_in, bool last_input_in_separately_signed_tx)
+  {
+    struct txin_signature_size_visitor : public boost::static_visitor<size_t>
+    {
+      txin_signature_size_visitor(size_t add) : a(add) {}
+      size_t a;
+      size_t operator()(const txin_gen& /*txin*/) const   { return 0; }
+      size_t operator()(const txin_to_key& txin) const    { return tools::get_varint_packed_size(txin.key_offsets.size() + a) + sizeof(crypto::signature) * (txin.key_offsets.size() + a); }
+      size_t operator()(const txin_multisig& txin) const  { return tools::get_varint_packed_size(txin.sigs_count + a) + sizeof(crypto::signature) * (txin.sigs_count + a); }
+      size_t operator()(const txin_htlc& txin) const      { return tools::get_varint_packed_size(1 + a) + sizeof(crypto::signature) * (1 + a);  }
+      size_t operator()(const txin_zc_input& txin) const  { return 96 + tools::get_varint_packed_size(txin.key_offsets.size()) + txin.key_offsets.size() * 32; }
+    };
+
+    return boost::apply_visitor(txin_signature_size_visitor(last_input_in_separately_signed_tx ? 1 : 0), tx_in);
+  }
+  //---------------------------------------------------------------
   size_t get_object_blobsize(const transaction& t, uint64_t prefix_blob_size)
   {
     size_t tx_blob_size = prefix_blob_size;
 
     if (is_coinbase(t))
+    {
+      if (is_pos_miner_tx(t) && t.version > TRANSACTION_VERSION_PRE_HF4)
+      {
+        // Zarcanum
+        return tx_blob_size;
+      }
       return tx_blob_size;
+    }
 
     // for purged tx, with empty signatures and attachments, this function should return the blob size
     // which the tx would have if the signatures and attachments were correctly filled with actual data
@@ -229,10 +252,12 @@ namespace currency
     bool separately_signed_tx = get_tx_flags(t) & TX_FLAG_SIGNATURE_MODE_SEPARATE;
 
     tx_blob_size += tools::get_varint_packed_size(t.vin.size()); // size of transaction::signatures (equals to total inputs count)
+    if (t.version > TRANSACTION_VERSION_PRE_HF4)
+      tx_blob_size += t.vin.size(); // for HF4 txs 'signatures' is a verctor of variants, so it's +1 byte per signature (assuming sigs count equals to inputs count) 
 
     for (size_t i = 0; i != t.vin.size(); i++)
     {
-      size_t sig_size = get_input_expected_signature_size(t.vin[i], separately_signed_tx && i == t.vin.size() - 1);
+      size_t sig_size = get_input_expected_signature_size_local(t.vin[i], separately_signed_tx && i == t.vin.size() - 1);
       tx_blob_size += sig_size;
     }
 
diff --git a/tests/core_tests/chaingen_main.cpp b/tests/core_tests/chaingen_main.cpp
index 6b794341..8a1e145f 100644
--- a/tests/core_tests/chaingen_main.cpp
+++ b/tests/core_tests/chaingen_main.cpp
@@ -772,8 +772,6 @@ int main(int argc, char* argv[])
     MARK_TEST_AS_POSTPONED(before_hard_fork_1_cumulative_difficulty);
     MARK_TEST_AS_POSTPONED(inthe_middle_hard_fork_1_cumulative_difficulty);
 
-    MARK_TEST_AS_POSTPONED(zarcanum_basic_test);
-
 #undef MARK_TEST_AS_POSTPONED
 
 
diff --git a/tests/unit_tests/basic_struct_packing.cpp b/tests/unit_tests/basic_struct_packing.cpp
index 54521528..7d75ff8d 100644
--- a/tests/unit_tests/basic_struct_packing.cpp
+++ b/tests/unit_tests/basic_struct_packing.cpp
@@ -84,9 +84,10 @@ TEST(tx_signatures_packing, 1)
 
   {
     // empty NLSAG
-    // v(0) + (1 + v(0) + 0 * 2 * 32) = 3                                                    
+    // v(1) + (1 + v(0) + 0 * 2 * 32) = 3                                                    
     sigs.clear();
     sigs.emplace_back(std::move(NLSAG_sig()));
+    ASSERT_EQ(3, t_serializable_object_to_blob(sigs).size());
     ASSERT_EQ(3, get_object_blobsize(sigs));
   }
 
@@ -96,14 +97,28 @@ TEST(tx_signatures_packing, 1)
     sigs.clear();
     for(size_t i = 0; i < 128; ++i)
       sigs.emplace_back(std::move(NLSAG_sig()));
+    ASSERT_EQ(258, t_serializable_object_to_blob(sigs).size());
     ASSERT_EQ(258, get_object_blobsize(sigs));
   }
 
+  {
+    // 128 10-ring NLSAGs
+    // v(128) + 128 * (1 + v(10) + 10 * 2 * 32) = 82178
+    sigs.clear();
+    NLSAG_sig nlsag = AUTO_VAL_INIT(nlsag);
+    nlsag.s.resize(10);
+    for(size_t i = 0; i < 128; ++i)
+      sigs.push_back(nlsag);
+    ASSERT_EQ(82178, t_serializable_object_to_blob(sigs).size());
+    ASSERT_EQ(82178, get_object_blobsize(sigs));
+  }
+
   {
     // empty ZC_sig
-    // v(0) + (1 + 32 + 32 + (1 + 10*32) + 32) = 99
+    // v(1) + (1 + 32 + 32 + (1 + 10*32) + 32) = 99
     sigs.clear();
     sigs.emplace_back(std::move(ZC_sig()));
+    ASSERT_EQ(99, t_serializable_object_to_blob(sigs).size());
     ASSERT_EQ(99, get_object_blobsize(sigs));
   }
 
@@ -113,6 +128,7 @@ TEST(tx_signatures_packing, 1)
     sigs.clear();
     for(size_t i = 0; i < 128; ++i)
       sigs.emplace_back(std::move(ZC_sig()));
+    ASSERT_EQ(12546, t_serializable_object_to_blob(sigs).size());
     ASSERT_EQ(12546, get_object_blobsize(sigs));
   }
 
@@ -124,6 +140,7 @@ TEST(tx_signatures_packing, 1)
     sigs.clear();
     for(size_t i = 0; i < 128; ++i)
       sigs.emplace_back(zc);
+    ASSERT_EQ(53506, t_serializable_object_to_blob(sigs).size());
     ASSERT_EQ(53506, get_object_blobsize(sigs));
   }
 }