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In Forza Motorsport, driving the car is only half the fun. Once you’ve driven around all the tracks, you’ll notice that some of the computer-controlled cars are just so much faster…time to take advantage of Forzas awesome tuning section.
There are so many tuning adjustments in Forza Motorsports that it can take some time to find that ‘perfect’ setup. Below we list all of the tuning options and tips on adjusting to benefit your car.
Aerodynamics
There are a couple different options in most aero packages, of which only 2 make that big a difference. They are:
– Air Dam:
• For the front. The air dam is mounted to the bottom of the front bumper to divert air around the sides or over the hood of the car. As a rule, the more angle the front air dam has, the more down force (equaling turn-in) it will provide. This will, however, create more drag and lower your top speed.
– Wing:
• For the rear. Wings are mounted to the rear deck lid, however, on a hatchback or similar it could be mounted to the roof. A wing is set off the actual body of the car, usually on mounts (wing mounts). A wing helps provide down force to the rear of the car. The more angle you give your wing, the more down force it will have, creating more traction to the rear of the car. The less angle, the less down force. More down force also means more drag, and less top speed. Less angle, less drag, more top speed.
– Spoiler:
• For the rear. Same as a rear wing, but it is mounted directly to the trunk (or roof) of the car. It is unusual to have both a spoiler and wing option. Same aero rules apply as a wing.
– Side Skirts:
• These small panels are mounted on the side of the car, between the front and rear tires, to the lower edge of the body. The skirts keep air flowing around the outside of the car, instead of under it. This will create a smoother airflow around the car, slightly increasing your top speed.
– Diffuser:
• For the rear. Rare on anything other than a Formula 1 car (or similar), the diffuser is mounted under and at the rear of the car. The diffuser channels air out the back, creating an immense amount of down force to the rear of the car. This help this type of car corner at higher speeds.
Anti-Roll Bar
The purpose of an anti-roll bar is to control body roll through a corner. A thicker bar equates to less body roll, a thinner bar is more body roll. In general, a thicker bar will make a car more agile, more sensitive to steering inputs. A thinner bar will make a car more lazy, a little more forgiving.
– Anti-Roll Bar, Front:
• A stiffer bar may take away steering entering a corner, but provide a little better exit steering. Start soft.
– Anti-Roll Bar, Rear:
• On the rear, a stiffer bar will allow the car to rotate through the corners better and should square the car up out of the corner. A softer bar will lock the rear end in, even resulting in under steer out of a corner. Start soft.
Use the Anti-Roll Bars as a fine-tuning adjustment instead of a ‘crutch’ for an ill-handling car.
Brake Bias
First off, we must understand something important:
Your brakes do not stop your car. Your tires DO top the car. While changes to different parts of the brake system may enhance the system characteristics, softer, stickier tires are the only real way to decrease stopping distances.
So, brake bias is, basically, setting the brakes to be stronger in the front or rear.
– Brake Bias, Front:
• More front brake bias can actually slow the car down a little faster (due to weight transfer) and help keep it under control. To much, however, can cause the front tires to load up, resulting in under steer.
– Brake Bias, Rear:
• More rear brake bias will cause the car to be ‘loose’, or unstable, when braking.
The correct brake bias setting depends on your driving style and how much brake you use entering a corner. You want to slow down fast, but still have control (and steering) through the entrance of the corner. A good starting setting is 40% – 45% front.
Camber
Camber is the inward or outward vertical tilt of the top of the tire. Negative camber is the tilt of the top of the tire towards the center of the vehicle (used often); positive camber is the tilt of the top of the tire away from the center of the vehicle (used VERY rarely). Proper camber adjustments are very critical for achieving maximum cornering speeds.
– Camber, Front
• FWD cars: Because a FWD car uses the front wheels for steering and acceleration, camber adjustments must be made in VERY small increments. Start with -.5 to -.7 degrees of camber. Remember, to much camber will affect straight line acceleration.
• 4WD cars: Because of the additional drive to the rear wheels, you can be a little more aggressive with your camber settings than a FWD car. Start with -1 to -1.2 degrees camber. Note: if you have to much front camber you will overheat the front tires. This will cause your car to push more in the corners.
• RWD cars: You can be much more aggressive with your front camber adjustments on a RWD car. Start with -1 to -1.5 degrees.
Be careful not to set your camber to aggressively (above 3 degrees). This will cause the outside tire (in a turn) to roll past the contact patch, reducing steering. You can pull up your Tire Wear Indicator to see how your camber is affecting your tires (green is good, red is bad). If you see red, reduce the front camber setting.
– Camber, Rear
• FWD cars: On a FWD car, the rear wheels are only along for the ride. You can start with the rear camber at -.2 to -.5. Depending on the class you are running, you will need to adjust the camber to either free up the car (less negative camber) or lock it in (more negative camber).
• 4WD cars: Less rear camber will allow a 4WD car rotate through corners better. It will also allow a 4WD car to hook up out of a corner, resulting in better acceleration. Less rear camber will also allow you to run more front camber. Start with -.1 to -.5 rear camber.
• RWD cars: Be conservative. There is a fine line when setting rear camber. More rear camber will negatively affect acceleration & braking, but lock it in the corners.
Caster
Caster is the leaning front to back (vertically) of the front axle. Positive caster is when the wheel is tilted back toward the rear of the vehicle. Negative caster is when the wheel is tilted forward toward the front of the vehicle.
More (positive) caster will make your car easier to drive, and stable on the straights and bumpy sections. Less (positive) caster will make your car react quicker to steering inputs. It will also give it more front bite in the corners. Less caster will make your car twitchy on the straights and out of corners.
There are NO circumstances where negative caster will be used (except, possibly, 4WD or FWD drag racing).
Differential
The differential is a gear assembly located at the rear of the car. It’s purpose is to distribute torque to the rear wheels under acceleration.In some games, you are allowed to change the differential gears, allowing different ratios for different size tracks. In other games, you are only allowed to adjust when the diff ‘locks’ in either acceleration or deceleration. We’ll discuss both briefly.
– Gear Adjustment:
• If you can adjust the F.D. (Final Drive) of the differential, remember these key notes:1. Smaller number (ie, 2.5) equals a smaller ratio, or quicker acceleration. This also means, however, less top speed and, in some cases, lower fuel mileage. Used mostly for short tracks or tracks with a lot of low speed turns.2. Higher number (ie, 6.5) equals a taller ratio, or higher top speed. This also means slower acceleration. Used on tracks with long straights (or ovals).
– Limited Slip Adjustment:
• As mentioned before, some games (like Forza Motorsports), allow you to adjust when the rear (or front) diff ‘locks’. This creates a posi-traction rear end. Posi-traction rear ends are designed to provide traction when one wheel has more traction than the other. This is what is adjustable…how much wheelspin is needed before the differential ‘locks’.
– Acceleration, Front: (FWD/4WD)
• Increase this setting to increase under steer, decrease to reduce under steer.
– Acceleration Rear: (FWD/4WD/RWD)
• Increase this setting to increase oversteer, decrease to reduce oversteer.
– Deceleration Rear: (4WD/RWD)
• Increase this setting to reduce off-throttle oversteer, for instance, entering a corner. Decrease this setting to increase off-throttle oversteer. Set correctly, this setting will help a car rotate though the corner with a small amount of drift.
– Center Differential Adjustment:
• Most 4WD car come with a center differential adjustment. When a 4WD car accelerates, weight is shifted to the rear wheels (especially high-powered vehicles). That lightens the load on the front, causing the front wheels to spin, wasting power. The center differential adjustment adjusts the power transfer between the front and rear drive wheels.
Ride Height
Ride Height is the distance measured, in inches, from the bottom of the chassis to the ground. The lower your ride height, the lower your CG (center of gravity). The lower the CG, the lower the overall vehicle weight will be to the ground. The lower the weight, the less weight transfer will occur during cornering.
– Front:
• If the ride height is set to low, it will bottom out and result in a push. Either raise the front or switch to a stiffer spring. Remember, however, that if you raise the front, you will also change the amount of roll the front of the car will have.
– Rear:
• If the ride height is set to low, it will bottom out and could spin. Either raise the rear or switch to a stiffer spring. Remember, if you raise the rear, you will also change the amount of roll the rear of the car will have.
Also:
– Front:
• In general, the higher the front of the car is (compared to the rear), the more aggressive the car should be. This is, of course, dependent on the rest of the setup.
– Rear:
• In general, the higher the rear of the car is, the more planted the rear should be. This is because more air is now flowing over the rear wing (as it is now higher in the air). Also, because of this, it will reduce top speed. If you run a slightly higher rear end, you should be able to lower the wing setting.
Shocks
Shocks are designed to control the suspensions up (bound, or compression) and down (rebound, or droop) movement caused by bumps in the road. They also play a major roll in controlling how quickly weight transfers during acceleration and braking. In general, the stiffer the shock, the less grip that end of the car will have in the corners.
Understanding Bound/Compression and Rebound/Droop is very important to tuning shocks. Basically, Bound/Compression is pushing the shaft into the shock (making it shorter), and Rebound/Droop is pulling the shaft out (making it longer). On the track, when you accelerate, the front of the car raises (rebound) and the rear squats (bound). When you brake, the front dives (bound) and the rear raises (rebound). Now, tuning that to win is another story.
– Front:
• More bound will result in more weight transfer, which will allow the front to dive more into a corner. Remember, to soft will cause the car to bottom out.
• Less bound will prevent the front from diving quickly, which will reduce steering into a corner.
• More rebound will help keep the front tires in contact with the ground under acceleration, resulting in better on-power steering.
• Less rebound will lighten the front end under acceleration, causing a car to under steer out of corners. This may also make a car unstable during acceleration.
– Rear:
• More bound will result in more weight transfer, which will allow the rear to squat under acceleration. This may cause the car to under steer exiting corners. This will help, however, in straight line acceleration.
• Less bound will result in a stiffer rear shock and can cause the car to be unstable under power.• More rebound will help lock the rear end in under braking, possibly to the point of slight under steer.
• Less rebound will help the car to rotate in the corners, but at the cost of stability.
Springs
The general purpose of the springs is to keep the car level during acceleration, braking, and cornering. The springs determine how much weight is transferred to each end of the car.
– Front:
• Stiffer Springs:
This will reduce dive into a corner. To stiff will result in under steer.
• Softer Springs:
This will allow more dive into a corner. To soft will result in the front bottoming out. A higher ride height (or stiffer anti-roll bar) will allow a much softer spring.
– Rear:
• Stiffer Springs:
This will reduce squat under acceleration, which can cause an on-power oversteer. This may also reduce stability.
• Softer Springs:
Softer rear springs will induce an on-power under steer, or push. To soft could cause the rear to bottom out. A higher ride height (or stiffer anti-roll bar) will allow a much softer spring.
Tire Pressure
In all racing, tires are about 80% of a car’s setup. The wrong tire can negate an entire setup. In fact, all the setup changes you make to a car are to benefit the tires you are using.Tire pressure is simply how much air you have in a tire. The hotter a tire gets, the more pressure that tire will have. You can use this to help set your cold-tire pressure. If you know that your tires work best at 30psi, you might set the cold-tire pressure at 25psi. Experimentation here is key.Tires with to much pressure can become over-inflated. Tires with to little pressure can become under-inflated.
– Front:
• Over-inflated tires can cause a lack of grip and induce under steer. They will, however, run cooler, have less drag and allow higher speeds.
• Under-inflated tires will give better grip, but can also result in excessive heat in that tire, causing more wear. They can also reduce speeds to the excess drag.Also note that lowering the tire pressure also lowers the overall ride height of the car.
Toe
Toe is the alignment of the front (or rear) tires in relation to the centerline of the chassis. Zero Toe is the front (or rear) tires pointing straight ahead. Toe-In is the front of the front (or rear) tires pointing in toward the centerline of the chassis. Toe-Out is the front of the front (or rear) tires pointing away from the centerline of the chassis. Toe is used to increase or decrease steering and steering response.
– Front:
• Toe-In will decrease steering into a corner, but add it (slightly) coming out. It will also stabilize the car under acceleration.
• Toe-Out will increase steering into a corner. Toe-Out will also cause the car to wander under acceleration and on the straights. In either case, Toe will also reduce overall top speed.
– Rear:
• Toe-In will result in less on-power steering, or less steering out of a corner.
• Toe-Out (or 0 Toe) will result in more steering into a corner, but at the cost of stability. Zero-Toe is will yield the best straight line speeds.
Transmission Ratio
The transmission is designed to change transfer engine power to the wheels through a series of gears. Most cars have either an automatic or manual (stick) transmission, and have between 4 and 6 gears (for this discussion, we’ll use 6 as our number). In most games, you have not only adjust the ratio of all 6 gears, but the Final Drive (F.D.) ratio also.
– Final Drive (F.D.):
• The F.D. can be adjusted to scale up (or down) all 6 gears together as a group. All together, you can tune your transmission for acceleration or top speed. The lower the F.D. number (ie, 2.50), the less torque but more top speed, good for tracks with long straights or ovals. The higher the F.D. number (ie, 6.50), the more torque, but less top speed. Use this for tight, winding tracks.
– Gears, 1st – 6th:
• As well as the F.D., you can fine tune your gearing though the individual gears. For tighter tracks, you might lower the F.D. ratio (remember, higher number) for more torque, but up the 4th, 5th or 6th individual gear to get a little more top end. For longer tracks, you might raise the F.D. ratio (lower number) for more top end, but lower the 1st, 2nd or 3rd individual gear to get a little more rip out of the slower corners. This is trial and error.
One more thing on Gearing. Your F.D. and individual gear setting will depend on the power you car has. If it is a lower-powered car, tuning for more speed will significantly hurt your bottom end. It may also not be able to hit the speeds you want because the motor doesn’t have the power (or torque) to pull it through the gears. Gearing on lower-powered cars is a lot more crucial than higher-powered vehicles.