GT7 offers a myriad of possibilities when it comes to tuning. Performance parts, aero components, and even engine swaps, you can turn pretty much any car into a pure track machine, and craft it towards specific uses.
GT7 Tuning Shop
If you are starting with a road car, the first thing you will probably do is go to the Tuning Shop to buy parts, modifications and tires to improve its performance. The shop is divided into different tiers, each one unlocking as you progress your collector level and offering more advanced parts, with the Extreme section unlocking at level 50. You can also buy a brand new engine and a complete body to refresh a car that has worn out too much.
Be careful: some engine modifications cannot be removed without buying a new engine, and weight reduction / body rigidity are completely permanent with no way to remove them. If you can, get another of the same car before doing permanent modifications in case you need to enter a race for stock cars.
Most parts will change the Performance Points of your car, so if you’re shooting for a specific PP target to comply with racing regulations, buying different types of the same part, like suspension or turbos, can be useful. Sometimes, not using the most expensive version of the part can be a good trade off to optimise certain aspects of performance you wish to prioritise. For instance, using a Sport Suspension instead of the fully adjustable variant can give you more PP budget to get softer tyres or more power.
Delta is the first ever tool that gives you the ability to analyse your data in extreme detail, giving you the opportunity to gain lap time like never before.
Each part comes with a useful description, telling you the potential adjustment range and different effects. Pay attention to this especially with permanent engine modifications: for instance, cams will shift the RPM range higher comparatively to a stroker kit which will increase power over a wider band, but at lower RPM. Note that every part from the extreme category overrides parts from previous tiers, and that the Carbon Ceramic brake kit performs identically compared to the Slotted and Drilled brake kits.
You can also buy a power restrictor and ballast to control your cars specifications and PP, and drifters can get a hydraulic handbrake plus a steering angle kit to unlock their full potential.
GT Auto Shop
GT Auto is another section that provides different services. Strangely, Car Maintenance & Service does not offer solely options to maintain your car into shape, but also the 2 most extensive permanent modifications you can perform: widebody modification to get slightly more tyre under the fenders, and engine swaps.
Those are quite expensive, and will severely limit your ability to participate in lobbies with extensive regulations, but can transform cars who get those options into absolute rocket ships. Engine swaps generally provide an unbeatable performance increase to PP budget ratio, but some cars can become uncontrollable with too much power, and the Escudo engine swap comes with an insane amount of turbo lag that will make a Lancer Evolution X actually worse than with the original engine tuned up.
Car Customisation focuses on aesthetic parts, most of which are purely esthetic. However, there are a few options that will affect performance in a significant manner. Wheels will impact handling depending on the sizes you select. Wheel diameter has a small effect on steering feel, with thinner tyres feeling sharper but more twitchy, while wheel offset will give you a bit more grip, especially if you have a widebody modification. Wheel width is more for looks, and will visually stretch the tyres.
Front bumper / lip options will increase front downforce and unlock adjustment, while rear wing will do the same for the back. On some cars, later wing options can give a higher base downforce and max adjustment – the custom wing option will always give you the maximum amount possible, regardless of which size and endplate option you select. Some cars have rear diffuser options (rear lips sometimes count) that increase the general level of downforce across both ends.
A last part that does not technically change the car performance, but could increase yours as a driver, is light bulb color. The aftermarket variants all have the same brightness, but can be better than the original lighting on older cars. Plus, everyone’s vision is different, and some people might have an easier time making out objects and shapes in yellow lighting at night. Don’t hesitate to try them all and figure out which one you prefer.
Settings Sheets Explained
Slapping a bunch of parts on your car is not necessarily sufficient to get a good result. Some components will unlock a variety of parameters you can fiddle with, and in some cases, it can become absolutely necessary to make your build driveable. The car settings screen can be accessed from your garage, as well as race registration screen and lobbies.
First, know you can create several setup sheets, duplicate and rename them. This is very practical to save different builds for different situations, and for quick A to B testing. It’s good practice to always keep a duplicate of your current sheet until you properly validate changes.
It’s also important to know how the data sheet on the left of the screen works, as it contains useful information. Performance Points are calculated based on a simulation of the AI driving the car and performing several tests. While higher is often better, the AI is perfectible, and may end up penalizing fast setups that it cannot control for some reason.
This can go to the point where it is simply unable to complete the tests, which will give you a /!\ sign instead of a PP figure, which will prevent you from using the car yourself. AI also doesn’t necessarily shift optimally with engines that would require short-shifting, which can skew the acceleration figure.
Stability and Rotational G figures are the most useful things to look at here. These numbers will change depending on tyres, the type of suspension and differential, weight distribution and aero balance. For stability, negative means understeery, while positive means oversteery. In practice, the scale is limited to -1.00 but cars can go well beyond that, and -1.00 High Speed is not necessarily bad. 0 is effectively quite sensitive already, and positive values will make you feel like you’re going to meet your ancestors within the next few seconds. For Rotational G, it’s pretty self explicit: the higher, the better. The 3 different speeds evaluated are useful to tailor your setup towards a certain type of corners, according to the track you’re driving.
Note however that, to kill past exploits, these, along with PP, only take into account the default setting of adjustable suspension and differential. Effectively, that means you’re going to use this to evaluate the changes you’re making to your downforce and ballast position before you start tinkering with the chassis by trial and error methodology.
Regarding the available settings, the game offers you quick explanations about the theory of what each setting does. But nothing will replace actual testing and figuring out what works best for you. There are some best practices regarding the general scope of car setups though, the basis being to do A to B testing tweaking a single parameter, and using the 3 Ws rule to analyze your machine’s behavior : What (oversteer or understeer), where (corner entry / apex / exit + speed of the corner), when (under braking, coasting, throttle, steering…).
Downforce is generally the first thing you want to adjust, if available: that’s where most of your cornering performance will come from. Always start with the front maxed out to maximize turn-in, and adjust the rear wing until you have good high speed balance. If you have too much drag and your top speed is impacted too severely, come back and decrease both front and rear ends simultaneously. It’s important to get a ballpark of what your final downforce levels will be, because alongside tyre compound, that will condition how stiff you want your suspension to be.
When it comes to suspension, Gran Turismo 7 works with natural frequency instead of spring rates, which prevents you from looking at real-life data to try and replicate aftermarket suspension kits. Natural frequency is however a better way to represent accurately how stiff or soft the suspension will feel: it measures the speed of shock movement and oscillations, which is not only affected by spring rate, but also by the whole geometry of the shock / control arms / anti-roll bar assembly. By default, it is generally recommended that the natural frequency be slightly higher (stiffer) in the rear than the front.
Ride height, and especially rake, will hold the most drastic effects on the way your car behaves. Negative rake (lower rear) is also known to increase top speed in GT7, but positive rake is generally preferred for more incisive cornering. Toe angles, especially in the rear, generally yields evident results as well. Negative (front of the wheels pointing outwards, also called toe out) is useful to increase initial turn-in, but can reduce speed once the car is settled into long corners. Positive (or toe in) is generally used for stability under braking and acceleration (for rear wheel drive cars). The more you deviate from neutral however, the more you will scrub, which results in more tyre wear and reduced straight line speed.
Next comes the differential, which is a very important part to get right. It has a critical influence on how your car will behave on and off throttle. High values represent a locked diff, while low values represent an open diff. Overall, in Gran Turismo, you want your sensitivity to be as high as you’re comfortable with for acceleration to get predictable rotation under power, and as low as you can manage for braking to avoid entry understeer. Initial Torque depends on how much you want to be able to “switch” between an open behavior and a closed behavior, as higher values will trigger the mechanism quicker.
If you decide or need to use some ballast, know that you can position it towards the front or the rear to change the weight distribution. Generally, if you can avoid ballast, you want to run your car as light as possible, but if you’re stuck with it, weight distribution has a massive influence on the car’s behavior. Like downforce, set it up before your suspension.
If you need to restrict your power, you can change some of the engine parts, or you can use the ECU and the Power Restrictor to limit it. Looking at one of them will show you the power and torque curves. The effects of both are very different: the ECU will just decrease power and torque proportionally across the whole RPM range, effectively preserving the curve’s shape, while the Restrictor will starve the engine from air at high RPM and only erode the curve’s peak, while keeping higher power and torque at lower RPM, which usually results in less acceleration losses but higher top speed losses.
Depending on the regulations you’re trying to match, the best solution could be to focus on just one, or a combination of both. The Restrictor is generally best when you’re trying to achieve a specific power figure, while ECU output is more effective at reducing PP while preserving power. In practice, the ECU penalizes performance more per percent applied.
If you have a customisable transmission, figuring out good gear ratios is important to exploit your engine in the best possible way. With a peaky power curve for instance, you want close ratios to limit the RPM decrease when shifting to stay in the power band. Gran Turismo will show you the achievable top speed in each gear, and a graph with lines representing RPM on the Y axis and speed on the X axis. It is quite useful to spot the crossover points between gears. My usual gearbox has a very long 1st gear (especially with high power) and a very short last gear, with space between each gear slightly decreasing as you go up through them: if you don’t know what to do, try to aim for a similar looking graph.
The last major setting commonly available is brake bias. Negative shifts the bias to the front brakes for more stability and stopping power, and negative shifts it towards the rear for better trail braking. You can change that setting while driving with the MFD function, so not getting it right from the start is not a major problem. It’s also a great tyre management tool, and rear bias provides more energy recovery for hybrid cars featuring electric motors on the rear axle.
4WD cars also get to play with torque distribution, allowing you to make the car behave closer to a FWD or RWD if you wish so. Note however that cars like Nissan GT-Rs with ATTESA or Mitsubishi Lancers with AYC can be better kept OEM on that front, since their torque vectoring systems are highly advanced and manage torque distribution dynamically between individual wheels to improve cornering.
Tuning Conclusions
Car tuning in Gran Turismo is a vast domain with several layers, and although the setup options themselves might not be as extensive as in other simracing titles, it is still complex and deep.
Your best tools to thrive in that journey are a perfect understanding of the regulations you’re submitted to, good methodology, and a lot of testing and patience. After experimenting for a while, you will start noticing some patterns and figure out baselines that suit you.
While I personally believe that there is an absolute fastest configuration for a car and track combo, that theoretical perfect setup is incredibly lively, and only a handful of drivers would be capable of surviving it. Ultimately, consistency in racing is key, so you want to find something you can safely bring in one piece to the finish line.
