Gran Turismo 4

Prototype Info Bugs CarsAssets relating to cars that didn't make the cut, as well those that did make it. ManufacturersAssets relating to manufacturers that didn't make the cut, as well those that did make it. Regional DifferencesLicensing and marketing choices resulted in lots of changes between regions, while the Korean version strives to add some local content.

Post-Release#

Mazda MX-5 EditionA special edition demo of the game, featuring the then-concept/pre-production version of the third-generation Mazda MX-5.

Cheat Codes#

Several previously undiscovered cheat codes were found in 2023, nearly 20 years after the game's release. These codes are usable only after reaching in-game day 367.

• 10,000,000 Credits (GT Mode Screen): Select, Left, Right, Right, Down, Up, Up, Left, Down, Up, Right, Left, Down, L1, R1, Select
• Pass any license (License Selection Screen): Select, R1, Select, R1, Select, L2, L2, R2, R2, L1, Select, L1, Select
• Gold any specific license test (License Test Selection Screen): Select, Select, R1, R2, L2, L2, Select, L1, R1, Select, R2, L1, Select
• Gold any event (Event Course Selection Screen): Select, L1, Up, Up, Select, R1, Down, Down, Select, L2, Select, R2, Select

There is an extra code usable in the Mission Hall, which also adds 10,000,000 Credits. It is presumably implemented incorrectly and should instead allow completing any mission. The code is Select, R2, Select, R2, L1, L2, L2, Select, L1, R1, Select, R1, Select.

Special Settings#

A hidden menu can be accessed by going to the Options screen and inputting L1, Up, L2, Down, R1, Left, R2, Right, Start, Start on the second controller; the sound heard when entering a menu from the main menu will then be played to confirm the right input. Note that the code must be entered each time the player visits the screen.

The two secret options associated with the input are named Secret and Monitor, both part of Miscellaneous part of the Options menu.

Function Overview#

Secret (Special Settings)#

This portion of the menu works like the PS3-era secret menus, where available tracks and cars can be restricted, suggesting it's intended for kiosk-related uses.

• Specific Cars: Restricts the cars available in Arcade Mode to those in the Favorites list in Arcade Mode. This option is not available if no favorites have been yet defined.
• Specific Courses: Restricts the courses available in Arcade Mode to those set in Course Registration Settings, which is primarily an option related to LAN mode.
• Specific Opponents: Restricts the opponent cars chosen in Arcade Mode to those in the Favorites list in Arcade Mode.
• Specific Makes: Allows the game to be set to only feature a certain manufacturer. When this is the case, you cannot enter Gran Turismo Mode, and the title screen's background movie is changed to a generic one with the chosen manufacturer on top of the game logo on the title screen. Selecting none, the default option, reverts to normal gameplay. An example can be seen on the MX-5 Edition's title screen.

Monitor (Detail Monitor Settings)#

This portion of the menu allows you to adjust the camera and the display of the screen during races.

• Flag: Four flags can be chosen (FLAG_NONE, FLAG_ROTY, FLAG ROTX, and FLAG_ROTX|FLAG_ROTY). These appear to deal with settings on each horizontal/vertical axis, but it does not appear to affect anything.
• Zoom: Adjust the field of view, in range of 0.00 to 3.00. Does not affect the roof camera.
• Distance: Adjusts the distance from the viewpoint of the player's camera between 200 to 1200 millimeters; the default setting is 276 mm.
• Width: Adjusts the width of the display area, between 200 to 600 millimeters.
• Height: Adjusts the height of the display area, between 200 to 400 millimeters.
• Aspect: Adjusts the pixel aspect ratio, between 0.00 to 2.00.
• Overscan Factor: Obvious what it adjusts, the value is 0.00 to 2.00.
• Border Width (Left, Right, Top, Bottom): Adjusts the width of each side of the screen border in millimeters. The range of each is 0 (default) to 300 millimeters.

The default settings depends on the selected aspect ratio mode:

Setting the zoom option to 0.80 provides a field of view on all cameras that is very similar to that of the roof camera.

GT3 Leftover Parts#

The Mazda 787B '91 and Volkswagen New Beetle RSi '00 still have default turbocharger parts (and in case of the New Beetle RSi, matching sports and racing intercoolers) as carryovers from GT3 despite both cars' aspiration being corrected from turbocharged to naturally aspirated in GT4.

Unused Race Events#

There is an unused race event in the game called Road Going Formula (misspelled as "Road Going Fomula Cup" on the flyer card; the word "Cup" is also missing on the event's actual name). Judging from its filename (ex_roadgoing_0000), this was planned to be an Extreme Hall event. The event is present in the game's event database, and completing it would have awarded the Caterham Seven Fireblade '02.

• Description: "A heated battle between formula machines that race on public roads." (European English)
• Event Type: Single Race (5 Races)
• Regulations:

:* Cars Permitted: No restrictions

• Rival Cars:

:* Suzuki GSX-R/4 Concept '01

• Race #1: Laguna Seca Raceway

:* Number of Laps: 3

:* Rewards Table:

{| class="wikitable"

|- !Position !1st !2nd !3rd !4th !5th !6th |- |Credits |15,000 Cr. |7,500 Cr. |5,000 Cr. |4,900 Cr. |1,500 Cr. |800 Cr. |}

• Race #2: Grand Valley Speedway Reverse

:* Number of Laps: 3

• Race #3: Tokyo R246

:* Number of Laps: 2

• Race #4: Suzuka Circuit

:* Number of Laps: 2

• Race #5: Fuji Speedway 2005

:* Number of Laps: 2

Notes#

• The event's flyer features an image of the Caterham Seven Fireblade '02 (along with the only opponent car for the event, the Suzuki GSX-R/4 Concept '01), which is not actually defined as an opponent car due to the car having a "special" (restricted to Time Trials and 2-car races in the Arcade Mode, due to high polygon usage) status.

Unused Driving Missions#

There are 34 Driving Missions in this game, divided into four mission genres (The Pass, Three Lap Battle, Slipstream Battle, and One Lap Magic, which is divided into two parts for prize cars purposes). However, it seems that there were plans for a fifth type of Driving Missions called Chase Battle, each with six challenges, all of them seemingly themed after touge (mountain pass) racing, and are set on "rally" city courses, which typically is designed for two cars on the grid.

These missions also have description text for the pre-race screen, although in the US version of the game, Mission 36's and 38's pre-race text are duplicates of Mission 35's and 37's, respectively; as such, the text dumps for Mission 36 and 38 are from the European version.

Hidden Courses#

License Tracks#

The license-specific tracks in this game consists of the variations of the Driving Park Gymkhana (the normally accessible version is named gymkhana_free) track and the slalom variant of Fuji Speedway (before the 2005 redesign).

• fisco_slalom: Used in IB-6 and IB-7 License tests.
• gymkhana: Used in the B License Coffee Break test.
• gymkhana_maze: Used in the S License Coffee Break test.
• gymkhana_spiral_r: Used in the International B License Coffee Break test.
• gymkhana_spral (note the typo): Used in the A License Coffee Break test.
• gymkhana_super: Used in the International A License Coffee Break test, although the name suggests that it was originally planned to be S License's Coffee Break challenge.

Drivable Photo Travel Tracks#

To do: Test further the remaining tracks, or at least describe what xTimelessGaming did on the video below.

Watch on YouTubeAs it turns out, you can drive on some of the places used in Photo Travel mode by cheat methods as they are treated as tracks by the game. However, you can only go so far, as it's very limited on what you can actually drive on.

The following locations has been tested:

• Beacon Hills: Only some of the roads can be driven before the player hits the invisible walls.
• Brooklyn: A very short map; the player can only drive on the dock you're on, as there are barriers surrounding it.
• Grand Canyon: Like the Brooklyn map, by the size of the map here, it really shows how far you can go, which isn't much. You can drive on and off the cliffside though, so that's cool. The course map for this track is taken from the namesake rally course.
• Times Square: It is possible to go down most of the main strip here. The map is actually placed to the right of the New York course, as its logo is shown before you start and the map is displayed while driving.
• Tsumago: Short and cramped is the best way to describe this one, and you can only drive on some of the village's roads, not all.

Grand Canyon Short Track#

A track icon for Grand Canyon Short Track can be found in the game's track logo folder (GT4.VOL/piece/crs_logo). This rally track was used only in a Driving School test in Gran Turismo 4 Prologue and did not return for the game.

Unused Grid Slots#

Watch on YouTubeThe Las Vegas Drag Strip, although only used for 0-400 tests, has a functional grid placement for the left-hand side of the dragway (normally only the right-hand side is used). The AI also works in the left lane, although its behavior after crossing the finish line seems to vary depending on the way the drag strip has been forced:

• If a racing event edited to take place in Las Vegas is loaded, the AI at the left lane will attempt to drive into the right lane once the finish line is crossed (see video).
• If the drag strip is forced by overwriting the memory address used for course selection at the right time, the car at the left will stay within its lane well until the wall that separates both lanes ends, then both cars will attempt to drive into the rightmost wall crashing into it.

Additionally, the lap time counter for the left lane will only go between 90.00 (the default time when unused) to 99.99, after which it will roll back to 90.00.

Unused Rear Wing Support#

There are 222 cars that can have a custom rear wing installed from GT Auto's Wing Shop. On top of those, there are eight cars that normally does not allow installation of a rear wing, but allows installation of one if car-specific restrictions are removed (complete with proper wing placement and wing parts):

• Alfa Romeo Giulia Sprint GTA 1600 '65
• BLITZ ER34 D1 spec 2004 (D1GP) '04
• Ford GT LM Race Car '02
• Mazda MX-Crossport '05
• Mercury Cougar XR-7 '67
• Subaru IMPREZA Super Touring Car '01
• Subaru IMPREZA Rally Car Prototype '01
• Toyota SPRINTER TRUENO GT-APEX (AE86) Shuichi Shigeno Version '00

Eight additional cars have correct wing placement, but with missing parts if a rear wing is forcibly installed:

• Buick Special '62
• Chevrolet Corvette Convertible (C1) '54
• Ford Model T Tourer '15
• Mitsubishi CZ-3 Tarmac '01
• Mitsubishi PAJERO Rally Raid Car '85
• Nissan EXA CANOPY L.A.Version Type S '88
• Nissan Fairlady 2000 (SR311) '68
• Toyota RSC '01

Unused Wheel Codes#

Although aftermarket wheels do not usually appear in Today's Special section of GT Auto's Wheel Shop, they do have names in that format (two first letters signifying manufacturer, and a four-digit identifier number; in most cases, the first digits are always 02).

Unused Music#

GT3 Songs#

The Japanese version of the game features 26 hidden songs from (also the Japanese releases of) GT3, GTC, and GT4P, under the file names of race_jnn (where nn is a number; race_j14 is skipped). These are as follows:

Unused Jingles#

Three jingles seem to be either unused or included in a very early patch of the Japanese version of the game. These are the following tunes:

Unused Music#

Two cut music tracks are present in the original Japanese and Asian release. These are "Ride" by The Vines (race_20 in game files) and "Once You Go - You Go!" By Dimitri Shapko (race_56 internally). In addition to these, an unused credit is present for "Test Transmission" by Kasabian. Since one ID is skipped (race_19), it is very probable that is its spot.

Error Handler#

During the loading screen, if the game fails to read the disc, the clock in the loading screen will turn red. If the game does recover from this error (the game continues to attempt reading the disc every second), the clock will turn back to white again.

More rarely, if the game ever runs out of memory or fails to allocate memory when loading, the clock will turn blue.

Debug Screens#

This needs some investigation. Discuss ideas and findings on the talk page. Specifically: How to enable debug Screen?

Four debug screens have been found in the game, with varying results depending on the version. These have been tested on the European, Japanese and Online Public Beta (US) releases:

demo_movie#

Just a pitch black screen. Pressing START returns to the previous menu. Identical in all versions of the game.

language#

Only available in the European version, makes use of the background image featured in the language selection screen in GT4P, with now untextured selectable icons.

Selecting the 'Debug' option results in the text lines being replaced with their IDs, while selecting 'ENGLISH (US)' or any of the Eastern languages breaks all of the game's graphics, with the only working text being placeholders and the cars' names:

list_box#

Identical in the European and Japanese releases, and slightly different in the Online Public Beta, seems to be a test for menu mechanisms similar to those of the Music Theater menu.

• Items named after colors in a very, very long list can be selected with X/O, and de-selected with SQUARE/TRIANGLE.
• In some versions, selecting an item then selecting another one that is not right next to it also highlights all the items in-between.
• The L1/R1 buttons don't seem to have effect despite the on-screen indications.
• Selecting the button with the spinning GT logo brings the player to another screen with other five spinning GT logos in front of grey squares.
  • In OPB, this button features a spinning trophy, and the screen it goes to doesn't feature any objects.
• The other two buttons at the left of the screen determine whether or not the list is scrollable.

slide#

In the European and OPB versions, this screen tests the Slideshow mode with the same succession of images normally available in the Music Theater / Jukebox. The images appear successfully in the European version, while the OPB version can't display any images and softlocks after pressing Start.

In the Japanese release, loading this menu goes to the Music Theater.

Version Differences#

North American Reprint#

A late Greatest Hits reprint of the North American version with a version number of 2.00 in the SYSTEM.CNF file (as opposed to 1.01 in the original release and earlier Greatest Hits copies). The SYSTEM.CNF file has a modification date of June 26, 2007, suggesting this is a late rerelease indeed. The only changes in this version are alterations to the following course files inside GT4.VOL:

• 20r60r
• grandcanyon
• hongkong
• lasvegas
• newyork
• r_20r60r
• r_grandcanyon
• r_hongkong
• r_newyork

The actual impact of these changes is unknown.

Oddities#

Mazda RX-8 Concept (Type-II) '01#

Although the car is available in multiple colors in Arcade Mode, when the Mazda RX-8 Concept (Type-II) '01 is obtained from earning all silver times in the International B License, the color the player receives is always in RX-8 Yellow color, leaving all other six colors seemingly unused in GT Mode. All other license prize cars available in multiple colors, such as the Volkswagen Lupo 1.4 '02 (from finishing the National B License) and Jensen Interceptor MkIII '74 (from getting all gold in International B License), are given to the player in any of each cars' color choices.

Because of this oddity, the car's other colors were left seemingly forgotten in the later games, they became hidden and unused in the PSP game and completely absent from the PlayStation 3-era games of the series.

Additionally, if it or its predecessor, the Mazda RX-8 Concept (Type-I) '01, is forced to appear in the dealership, the car exhibits a different behavior from those without a listed sale price, in which the player can purchase the car at no cost instead of being blocked from doing so. An another case is for the Mazda MX-5 '05. If it is added to the dealership through adding an entry in the purchasable car list for Mazda dealer, it will act in the same manner as the two Mazda RX-8 Concepts, or rather, the player can acquire it for free.

Toyota 7 Race Car '70#

In Arcade Mode, it is possible to drive the Toyota 7 Race Car '70 on dirt or snow tracks, even without using the car switch glitch. However, doing so results in the car's wheels appearing to be hollow, with the car being difficult to drive as a result; additionally, when the replay is played back, the tire information is shown as "-/-".

If this is done in 2 Player Battle with Player 2 choosing the car in question, the tires will appear properly (although not fully fitting the car in size), with proper drivability.

Mitsubishi Lancer Evolution Super Rally Car '03 Intercooler Parts#

Despite the car being a Rally Car, it doesn't have the "regular" tuning options like the others racing cars. This one is the only racing car to have intercooler parts.

Dodge Viper GTS-R Team Oreca '00 Racing Exhaust#

If playing the North American version of the game, a free Racing Exhaust can be purchased for free for the Dodge Viper GTS-R Team Oreca '00. This is actually a GT3 leftover, since also here the car is affected by the same problem. This issue will not be fixed until Gran Turismo 5.

Citta di Aria in Arcade Mode#

For some reason, Citta di Aria is the only track that cannot be used in Arcade Mode's Single Race mode. However it can be selected in Time Trial and 2 Player Battle modes.