Forza Horizon 4 Car Setup

Today, we are gonna show you how you must set your car up for S1 class 900 point road racing. How to set 2008 Dodge Viper ACR properly.

Forza Horizon 4 Car Setup
Forza Horizon 4 2008 Dodge Viper SRT10 ACR

Forza Horizon 4 is one of the best racing games ever. It has a nice balance with simulation and arcade, also very nice graphics. Although, when you play online, if you want to win, you must set your car for yourself. You can also use people setups but, if you want to make yourself a setup you should pay attention to some variables.

Pick a car for Forza Horizon 4 road racing.

2008 Dodge Viper STR10 ACR

We will use a 2008 Dodge Viper SRT10 ACR to make a special setup for S1 Class road racing. But you can select any other car for any other class. Just remember, this setup is just for road racing. And we are suggesting you, buy a car in its own class. If you want to make a S1 road car, buy a stock s1 car, not below that.  Because you will be racing them! If you buy a A class or B class car, you need heavy upgrades. If you update that much, the car class will be upgraded. But not able to perform as stock S1 car. Because if you select a car like Volkswagen Golf 2003, and upgrade it for S1 class, it will be racing with that Dodge Viper of ours. Maybe in parameters, they will look like performing the same results but, that Volkswagen Golf will never be able to have a center of gravity like Dodge Viper. Or have a wheelbase like it. Maybe for another purpose, you can use a car from another class. But for road racing, best results come with cars in the same class.


Got your car? Good, now hit the open road!

Forza Horizon 4 2008 Dodge Viper STR10 ACR

It's very important to drive your stock car with no assist before you upgrade it. Driving your car stock is helping you develop your setup strategy for road racing. You should disable all your assists in your difficulty settings. Even disable your ABS assist if you are using a console. After that, you can understand the character of your car. After you disable your assists, you should drive it like you are racing, does it oversteer? Does it understeer? Does wheels spinning when you accelerate? All that information is very useful when you upgrade your car. If your car oversteering, that means you need to have more downforce on the back of your car or need to set your tyres up.


If your car understeer when you are turning a corner, that means you need more grip on your front tyres. You can do it with a front lip and side wings. Also, look for your cars gear setting. Can you reach top speed in last gear? How much time does it take to change gear? Does wheel spinning when you put the second gear? And at last, if you are using a console joystick for gaming, use brakes with no abs. You should be able to turn a corner comfortably without locking your tyres. If you are using a keyboard for gaming, tyres will be locked anyway so do not disable your abs assist. Calculate all of that information and keep it in your mind.


For Dodge Viper STR10 ACR, we can say its an understeering car (surprisingly), also it has not much power to reach top speed fast. But car grips like an angel. But has a small problem, car sliding that outer tyre when cornering. You can see the photo below. When we turn right, car's left tyre sliding like it shouldn't be and car's back is little bending comparing to the front.

Forza Horizon 4 Dodge Viper Sliding




How to upgrade your car parts in Forza Horizon 4

How to upgrade your car in Forza Horizon 4

For upgrading your car, you should know what is your car's pros and cons. For our 2008 Dodge Viper STR10 ACR pros are grip, acceleration, and downforce. But cons are more power needed and little understeering issue. Our car has a stock point of 866 points, so we need to focus on cons to make it perfect road racing car. So, for understeering RWD car, we must go for swapping drivetrain and make it AWD. With that, our car will be more balanced in cornering and it will launch better. But don't forget, if you swap your drivetrain to AWD, your top speed will be decreased. After we swap it, our car will still have 866 points. After that, we can focus on weight reduction. It is the most effective part of road racing car.


After we lighten it, we will put an additional front lip and side wings for downforce. Luckily, we don't need a back spoiler because it has its own spoiler can be set. Now, our viper reach points of 10 in acceleration, launch and braking. Handling point is at 9,6. We can improve handling more but let's focus on more power. Because for a S1 car, our little monster reaches more than enough. And for last big upgrade, we use race cams and valves for more power and more rpm. After that, the car's performance point will be 901. Whoops, for that situation, we can use a roll cage. Weights 23 kg, but adding stiffness to the car and will help to bend problem at the back of the car. That way we stuck at 899 points. Lucky for us, all drivetrain upgrades cost us just 1 point, and we can finish our job at upgrade shop.


For our situation, we need a S1 road car and our car was having trouble with understeer and needed more power. For your own car, you must decide what you will need. Basic rules of road racing are lightning, gripping and cornering speed. Find your own setup, make it fast and balanced. You will be winning any race if your setup is right.


Car stats will look like this after upgrading;

Forza Horizon 4  car upgrading guide




Got your upgrades? Good, let's hit the road again on Forza Horizon 4's open world!

Hitting the road is very important without touching anything. Because you will learn your stock parts parameters. You can see if you did fix the problems or not. See the dynamics of the car again. In Forza Horizon 4, developers are aimed to have a simulation like gaming. So if you can calculate your problems, you can solve them too. When we did hit the road, we can see our viper is not having an understeering issue but sliding both front wheels. That may sound like a problem but it's not because G-Force load is dividing both front wheels, means more traction. See that in picture below;

Forza Horizon 4 Dodge Viper

So we did actually change the dynamics of the car and add more power to it. Let's go to step 2 and calculate our car's dynamics and find the problems again. From now on, we can use The Telemetry on Forza Horizon 4. You can open the telemetry menu by clicking the T button on your keyboard. Change menu to 'Tyres, MISC.' part and look at your stats when you are racing your car. When turning most corners, your front wheel camber needs to reach the point 0. It's tricky to see it, but you can see it if the minus in front of the degree is showing and disappearing. If you see that minus character showing and disappearing very quickly, that means your alignment is correct. If it's not, you can make it right with using caster tune in car tuning menu.



Why should you use caster instead of camber? How to set your car wheel alignment right

Many people will suggest, you should use camber alignment for correcting wheel alignment setup. But after using camber alignment your car's front wheels will not be balanced well. For back tyres, using camber alignment is okay because your car's back tyres are not steering. So for steering ones, if you use camber alignment for fixing the setup, your front tyres will look like this when you are cornering;


Cornering at Forza Horizon 4

So that way, as you can see the inner wheel is not gripping efficiently. That way maybe your cars outer wheel gripping, but like our stock Dodge Viper it will be having problems with dividing G-Force to two. But if you fix it with caster angle, you can divide that G-Force perfectly balanced as the picture below.




Cornering at Forza Horizon 4

As you can see, the inner wheel is more straight and because of the position, it will be performing more grip as the G-Force power increases. Also, that setup will divide the power of G-Force of equal 2 parts. So if you need to set the alignment of your front tyres with caster, you will gain more grip. That is not much effective in Forza Horizon 4 but still will help a lot.



How must you tune your car in Forza Horizon 4

Tuning is very important for racing. It helps to decide your car's character for more cornering, drifting or drag racing. As we are going for road racing, we must set it up for it. The tuning section contains 9 menus inside it. These are tyre pressure, gearing, alignment, anti-roll bars, springs, damping, aero, brake and differential. We will use to set up our car as F1 engineers do. We will formulate it and set it up. First of all;



Tyre Pressure

Type pressure is important because of the tyre heat. You can't transmit your car's power and handling potential to the road without the right tyre setup because of tyre pressure affects a tyre's peak grip, responsiveness and wear. Adjust front tyre pressure when the tyres are cold so they reach peak grip once they have heated up to race temperatures. Setting your tyre pressure low is cause more heat for your tyres but it will reduce responsiveness. The default setup is 30 PSI, but you can change it for yourself, and when you are racing, if tyres little hot for gripping, telemetry parameters will show bright yellow if your tyres have so much heat the parameters will turn red. So make sure you stay in no coloured zone when you are cornering and during acceleration. Tyre heat telemetry is in the photo below;

Forza Horizon 4 Car's tyre heat






Gearing is important for acceleration and cornering speed. Proper gearbox should use cars maximum power and make it reach the top speed. Gearbox has 2 main settings, one for the final drive, other is for setting each gear. First, you need to adjust the final drive of the gearbox. This is the output of the gearbox so this setting is change every gear's speed. Lucky for us, Forza Horizon 4 has the graphic for gears with speeds. Your setting should be fit all the gears in that graphic, also last gear should touch the maximum rpm at top speed. When you are done tuning final gear, it should look like this;

Gear tuning in Forza Horizon 4


 The second part of gear tuning is more tricky. You need to prevent wheel spin at launch. Also, you need to work with the torque curve of your car. Adjusting individual gear ratios affects acceleration and top speed. A higher ratio makes quicker acceleration, lower ratio gives you higher top speed. But how should set this up? Well, first of all, you need to set first gear for preventing too much spinning at launch. If your car's rpm is bouncing on rpm limit too much, you should lower your first gear ratio. If you need more power when launching, you need a higher ratio. For AWD cars, tyres are not able to spin too much when the car launches. So that way you can set a higher ratio to your car. For other gears, there is a formula. The top-secret formula is setting your gears above the torque curve of your car. For our car, the torque curve is like this;


Forza Horizon 4 Dodge Viper's Torque Curve


So as you can see, our torque curve's top is around 5,500 RPM, that means we should use that area for acceleration and set gears for it. So when we put it to next gear, we want to start it around 5,500 RPM. That may look like we are not using torque curve efficient, but actually we are using car's HP for acceleration so as the curve shows us  HP is always increasing, that will be efficient. So if you set your first 2 gears to not spinning, you can set the other gears for starting around 5,500 RPM. Of course, that is for our car Dodge Viper, you should find your own car's torque curve and set it for that curve. When you done tuning, it may get outsite of that gearing graphic again, set it with final ratio again to having maximum efficiency. At last, our gearing looks like this at the end;


Forza Horizon 4 Dodge Viper gearing setting

If your car is not much power to reach top speed with this setup, you can set last gear and previous gear to start higher RPM. It will help your car to reach top speed.




Alignment section has 3 different settings, those are setting for camber, toe and caster. Adjusting camber (the top to the bottom angle of the tyres) affects your car's grip, with that character of cornering will change. Also, the acceleration of your car will change. Negative camber (Tops of the tyres leaning inwards) reduce understeering and by that increase cornering, but it reduces straight-line grip. Positive camber (tops of the tyres leaning outwards) reduces oversteer, but it will make your car unstable. For the right setup, your camber in telemetry screen must reach 0 degrees of camber when you are cornering. But we recommend you to set it with caster degree as we write it before.


For toe alignment, you can leave it like that, but for people who wants to know, toe means the inward or outward angle of the wheels. Toe-in brings the fronts of the tyres closer together than the back of the tyres. This increase stability, but it reduces the turn-in response. Toe-out is opposite of toe-in, increase turn-in response, but makes your car more unstable. If you are using simulation mode for damage, avoid extremes because excessive toe-in or toe-out can wear tyres very quickly.


Anti-Roll Bars, Springs and Damping 

These are car's suspension settings and can be set with a simple formula. First, you need to find your cars weight ratio. It can be found at upgrade shop, select any upgrade and before you install it, click the Toggle button to see your vehicle's weight ratio. For our car is front-51%. Second thing you do is grab a calculator (really grab one), and calculate.

Anti-roll bars, Springs and damping can be stiff or soft. So you can use the formula to calculate how to set stiffness.

The formula is; ((Maximum stiffness-Minimum stiffness)x Your car's weight ratio)+minimum stiffness value. 

For the front, we use that 51% to multiply. Use the percentage between 0 and 1. 51% means multiply it with 0,51. For the rear, we use the rear percentage of weight ratio, which is 49%. With that formula, you can find your cars perfect setting for the suspension system. Also, that formula is used by formula 1 engineers.

And for ride height, road racing requires the lowest center of gravity, means the lower car will take corner better. So making your car low gets you more cornering power.




Aerodynamics is air flowing around a car creates lift beneath it, which impairs handling. Increased downforce can do better cornering, but it reduces the top speed of your car. However, you can set your own setting for yourself. if you still having trouble with understeer and oversteer at high speeds, aerodynamics is a very good solution for stabling your car. For us, we use the default value of downforce.



Brakes are very important if you are using a console joystick for playing the game. Adjust overall brake pressure so the tyres will lock under hard braking, but won't lock prematurely with just a small amount of pedal travel. Reducing total brake pressure increases the amount of pedal travel required to lock the tyres. If you reduce it too much, the tyres won't lock at all. But it will increase your braking distance. Set it up for your joystick.



The differential setting is dividing 3 for AWD cars, for RWD and FWD cars will have 2 settings menu. One is the centre of balance. That will decide how much power goes to rear tyres and front tyres. Usually, around 55% - 65% will perform very good.

Other settings are differential lock settings. This means how much speed difference allowed between right and left tyre. If you set it to 100%, your car will slide in corners, because the inner tyre will be speeding as the outer tyre. If you set it to 0%, your car will lose power when it turns, because of the difference is not important anymore, inner tyre will be spinning to much and take all the power from engine.

The right setting for this tune is up to you. Centre of balance must be considered with weight ratio and your car's tyres thickness. Differential lock for rear tyres default setting is 75%, which is a very good setting for road racing. Also front differential lock for accelleration must be near of 50%, but you can set it 0% for deceleration, because it effect sharp cornering at low speeds.



So this is pretty much it. If you set your car properly, it should be rocking Forza Horizon 4 servers. After you set your car up, you just need to set your visuals. For our setup with 2008 Dodge Viper STR10 ACR, you can find it with the share code of: 120 699 108. Happy gaming!

Forza Horizon 4 2008 Dodge Viper STR10 ACR