diff --git a/src/mame/drivers/spdheat.cpp b/src/mame/drivers/spdheat.cpp
index 0c2cc68bc21..8332348a98f 100644
--- a/src/mame/drivers/spdheat.cpp
+++ b/src/mame/drivers/spdheat.cpp
@@ -583,21 +583,21 @@ static INPUT_PORTS_START( spdheat )
 
 	PORT_START("IN0")
 	PORT_BIT( 0x0001, IP_ACTIVE_HIGH, IPT_BUTTON1 ) PORT_TOGGLE PORT_NAME("P1 Shift") PORT_PLAYER(1)
-	PORT_BIT( 0x0002, IP_ACTIVE_LOW, IPT_UNKNOWN ) // if this is ACTIVE_HIGH gear in Service mode will always show low gear, but your start will be slow as if in high gear regardless of above
+	PORT_BIT( 0x0002, IP_ACTIVE_LOW, IPT_UNUSED ) // if this is ACTIVE_HIGH gear in Service mode will always show low gear, but your start will be slow as if in high gear regardless of above
 	PORT_BIT( 0x0004, IP_ACTIVE_LOW, IPT_UNUSED ) PORT_NAME("Reserved 2")
 	PORT_BIT( 0x0008, IP_ACTIVE_LOW, IPT_UNUSED ) PORT_NAME("Reserved 1")
 	PORT_BIT( 0x0010, IP_ACTIVE_HIGH, IPT_BUTTON1 ) PORT_TOGGLE PORT_NAME("P2 Shift") PORT_PLAYER(2)
-	PORT_BIT( 0x0020, IP_ACTIVE_LOW, IPT_UNKNOWN ) // see above
+	PORT_BIT( 0x0020, IP_ACTIVE_LOW, IPT_UNUSED ) // see above
 	PORT_BIT( 0x0040, IP_ACTIVE_LOW, IPT_SERVICE2 )
 	PORT_BIT( 0x0080, IP_ACTIVE_LOW, IPT_UNUSED )
 
 	PORT_START("IN1")
 	PORT_BIT( 0x0001, IP_ACTIVE_HIGH, IPT_BUTTON1 ) PORT_TOGGLE PORT_NAME("P3 Shift") PORT_PLAYER(3)
-	PORT_BIT( 0x0002, IP_ACTIVE_LOW, IPT_UNKNOWN ) // see above
+	PORT_BIT( 0x0002, IP_ACTIVE_LOW, IPT_UNUSED ) // see above
 	PORT_BIT( 0x0004, IP_ACTIVE_LOW, IPT_UNUSED ) PORT_NAME("Reserved 3")
 	PORT_BIT( 0x0008, IP_ACTIVE_LOW, IPT_UNUSED ) 
 	PORT_BIT( 0x0010, IP_ACTIVE_HIGH, IPT_BUTTON1 ) PORT_TOGGLE PORT_NAME("P4 Shift") PORT_PLAYER(4)
-	PORT_BIT( 0x0020, IP_ACTIVE_LOW, IPT_UNKNOWN ) // see above
+	PORT_BIT( 0x0020, IP_ACTIVE_LOW, IPT_UNUSED ) // see above
 	PORT_BIT( 0x0040, IP_ACTIVE_LOW, IPT_SERVICE4 )
 	PORT_BIT( 0x0080, IP_ACTIVE_LOW, IPT_UNUSED )
 
@@ -782,12 +782,12 @@ void spdheat_state::spdheat(machine_config &config)
 
 ROM_START( spdheat )
 	ROM_REGION( 0x30000, "maincpu", 0 )
-	ROM_LOAD16_BYTE( "a55-04.ic37", 0x00000, 0x08000, CRC(bb1dd6b2) SHA1(f0d45f82e643fbc5cf6ec75fd8d7ae4c4b7d8b23) )
-	ROM_LOAD16_BYTE( "a55-01.ic26", 0x00001, 0x08000, CRC(7ee12547) SHA1(79395cc622a315c3b3c3000224e150311da8073d) )
-	ROM_LOAD16_BYTE( "a55-05.ic36", 0x10000, 0x08000, CRC(b396ef0b) SHA1(7a7f59faf4478c417f0928b22fb81462cb2628c2) )
-	ROM_LOAD16_BYTE( "a55-02.ic25", 0x10001, 0x08000, CRC(4b76870a) SHA1(6bc1a594e37e2e3f2f0b4f23ba9bd7c87c3a27d9) )
-	ROM_LOAD16_BYTE( "a55-06.ic34", 0x20000, 0x08000, CRC(900ecd44) SHA1(352b196bfe3b61cfbcdde72a03d3064be05be41e) )
-	ROM_LOAD16_BYTE( "a55-03.ic23", 0x20001, 0x08000, CRC(6a5d2fe5) SHA1(595cc6028dbd0ceaf519b9a5eddfeffa74e2d27c) )
+	ROM_LOAD16_BYTE( "a55-04-1.ic37", 0x00000, 0x08000, CRC(bb1dd6b2) SHA1(f0d45f82e643fbc5cf6ec75fd8d7ae4c4b7d8b23) )
+	ROM_LOAD16_BYTE( "a55-01-1.ic26", 0x00001, 0x08000, CRC(7ee12547) SHA1(79395cc622a315c3b3c3000224e150311da8073d) )
+	ROM_LOAD16_BYTE( "a55-05-1.ic36", 0x10000, 0x08000, CRC(b396ef0b) SHA1(7a7f59faf4478c417f0928b22fb81462cb2628c2) )
+	ROM_LOAD16_BYTE( "a55-02-1.ic25", 0x10001, 0x08000, CRC(4b76870a) SHA1(6bc1a594e37e2e3f2f0b4f23ba9bd7c87c3a27d9) )
+	ROM_LOAD16_BYTE( "a55-06.ic34",   0x20000, 0x08000, CRC(900ecd44) SHA1(352b196bfe3b61cfbcdde72a03d3064be05be41e) )
+	ROM_LOAD16_BYTE( "a55-03.ic23",   0x20001, 0x08000, CRC(6a5d2fe5) SHA1(595cc6028dbd0ceaf519b9a5eddfeffa74e2d27c) )
 
 	ROM_REGION( 0x10000, "audiocpu", 0 )
 	ROM_LOAD( "a55-17.ic11",  0x00000, 0x08000, CRC(43c2318f) SHA1(472e9cc68bb8ff3c5c3d4ec475491ad1a97261e7) )