diff --git a/Source/Core/Common/FatFsUtil.cpp b/Source/Core/Common/FatFsUtil.cpp
index f194dc22a3..88d746e8ea 100644
--- a/Source/Core/Common/FatFsUtil.cpp
+++ b/Source/Core/Common/FatFsUtil.cpp
@@ -26,6 +26,8 @@
 #include "Common/ScopeGuard.h"
 #include "Common/StringUtil.h"
 
+#include "Core/Config/MainSettings.h"
+
 enum : u32
 {
   SECTOR_SIZE = 512,
@@ -513,9 +515,13 @@ bool SyncSDFolderToSDImage(const std::function<bool()>& cancelled, bool determin
   if (!CheckIfFATCompatible(root))
     return false;
 
-  u64 size = GetSize(root);
-  // Allocate a reasonable amount of free space
-  size += std::clamp(size / 2, MebibytesToBytes(512), GibibytesToBytes(8));
+  u64 size = Config::Get(Config::MAIN_WII_SD_CARD_FILESIZE);
+  if (size == 0)
+  {
+    size = GetSize(root);
+    // Allocate a reasonable amount of free space
+    size += std::clamp(size / 2, MebibytesToBytes(512), GibibytesToBytes(8));
+  }
   size = AlignUp(size, MAX_CLUSTER_SIZE);
 
   std::lock_guard lk(s_fatfs_mutex);
diff --git a/Source/Core/Core/Config/MainSettings.cpp b/Source/Core/Core/Config/MainSettings.cpp
index 1a7c523d6e..7023ec411b 100644
--- a/Source/Core/Core/Config/MainSettings.cpp
+++ b/Source/Core/Core/Config/MainSettings.cpp
@@ -10,6 +10,7 @@
 #include "AudioCommon/AudioCommon.h"
 #include "Common/Assert.h"
 #include "Common/CommonPaths.h"
+#include "Common/CommonTypes.h"
 #include "Common/Config/Config.h"
 #include "Common/EnumMap.h"
 #include "Common/FileUtil.h"
@@ -175,6 +176,7 @@ const Info<bool>& GetInfoForSimulateKonga(int channel)
 const Info<bool> MAIN_WII_SD_CARD{{System::Main, "Core", "WiiSDCard"}, true};
 const Info<bool> MAIN_WII_SD_CARD_ENABLE_FOLDER_SYNC{
     {System::Main, "Core", "WiiSDCardEnableFolderSync"}, false};
+const Info<u64> MAIN_WII_SD_CARD_FILESIZE{{System::Main, "Core", "WiiSDCardFilesize"}, 0};
 const Info<bool> MAIN_WII_KEYBOARD{{System::Main, "Core", "WiiKeyboard"}, false};
 const Info<bool> MAIN_WIIMOTE_CONTINUOUS_SCANNING{
     {System::Main, "Core", "WiimoteContinuousScanning"}, false};
diff --git a/Source/Core/Core/Config/MainSettings.h b/Source/Core/Core/Config/MainSettings.h
index 546696476f..dd8f1632f8 100644
--- a/Source/Core/Core/Config/MainSettings.h
+++ b/Source/Core/Core/Config/MainSettings.h
@@ -9,6 +9,7 @@
 #include <utility>
 
 #include "Common/Common.h"
+#include "Common/CommonTypes.h"
 #include "Common/Config/Config.h"
 #include "DiscIO/Enums.h"
 
@@ -98,6 +99,7 @@ const Info<bool>& GetInfoForAdapterRumble(int channel);
 const Info<bool>& GetInfoForSimulateKonga(int channel);
 extern const Info<bool> MAIN_WII_SD_CARD;
 extern const Info<bool> MAIN_WII_SD_CARD_ENABLE_FOLDER_SYNC;
+extern const Info<u64> MAIN_WII_SD_CARD_FILESIZE;
 extern const Info<bool> MAIN_WII_KEYBOARD;
 extern const Info<bool> MAIN_WIIMOTE_CONTINUOUS_SCANNING;
 extern const Info<bool> MAIN_WIIMOTE_ENABLE_SPEAKER;