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Mr. hueyduey · Posted: Sun Aug 26, 2007 6:37 am Post subject:

This guide is primarily designed to help drivers learn to understand the physics of forza motorsport 2 in drifting situations. By no means am I an expert, but from my experience I’m trying by best to explain the game so that others may get the hang of drifting easier. Thanks goes out to BLKJ Mr.Fuji for helping me figure out what sh*t does, and using what he's told me to write this guide.

Drift physics and tips:
1. Turn has a maximum speed given its radius and length. It is up to a particular car with the amount of Gs it’s capable of carrying though the turn that determines this. It’s possible to drift a turn as fast as you can grip drive it, its due to corner acceleration out that limits drifting style as a means for competitive racing. For example in a drag race, the key is tire grip, if you spin the tires you lose grip and acceleration.

2. Braking in a straight line is the fastest way to slow down. Drift braking is different where brakes are applied to slide the rear end of the car out. This is done by braking while turning to get car to oversteer. Because the car tires are sliding rather than gripping in drift braking, more room is needed to slow the car down for drifting. Getting accustomed to a car and a particular track will take some time, using the braking assist will you determine how much room you need to brake before a turn. Turn off the assist once you get a hang of braking to oversteer. That way you can develop a natural feeling for getting a good entry speed and angle.

3. All drift techniques found here: http://forums.forzamotorsport.net/forums/thread/302495.aspx can be used to drift in forza. Most will come naturally to you, as you develop your own drifting style, but read them over and try new techniques.

4. Maximum drift angle is something that you’ll need to get a feeling for. There’s a limit to how much a car can slide before it reaches the point of non recovery. By non recovery I mean having to let completely off the throttle to regain control of the car. To achieve maximum drift angle is a combination of throttle and countersteer. There are times when both can be applied at 100%, but only for a split second and majority of the time this is not the case.

5. AWD cars are more forgiving than RWD cars during a drift, but RWD has the power to initiate a drift more naturally than an AWD car. (I’m not too good in this area, as I rarely use AWD to drift. if someone can help me explain this I would appreciate it.)

Buying upgrades:

You can go all out and pimp out your car with everything on it. There’s really no limit to how much horsepower a drift car can have. But when there’s too much horsepower it gets hard to control the car. As mentioned above in the physics a car is only capable of turning so fast based on the amount of Gs it can withstand. 2 cars with the same suspension and tires will take a corner as the same maximum speed, it is the acceleration out of turns and on straight portions of a track that makes one car faster than another. With that said more power isn’t necessarily better. Yes it takes more skill to drive a higher horsepower car, but sometimes its fun in a low hp car mashing the gas through every drift without having to worry too much about throttle control.

Buyers Guide:

What to buy? Do all your suspension upgrades, and weight reduction. For tires you can use whatever tires you prefer. I like to keep it true to drifting and use Y-compound street tires. In real life drift competitions restrict tires to be street tires, FMDA rules allow for anything under U class. But there’s nothing wrong with using racing tires. Tire width helps with traction. If you’re having a hard time getting traction on off the starting line or if you’re peeling out through 3rd or 4th gear, increase the width of the tires. Rim size and style increases/decreases weight but I don’t think it’s noticeable, go what whatever makes you happy.

When buying parts check the power band chart to see how parts affect your car’s horsepower and torque curves. An erratic curve can make you give your car the unwanted jump in power as your getting on the throttle. Exhaust, intake, ignition, fuel, and intercooler generally boost the powerc urve evenly. Block and port/polish increases power and increases the max redline. Cams and forced induction should be chosen, 1 or the other. Cams will increase your power at higher RPMs and increase your redline. Forced induction increases power in the middle-to-high RPM band w/o increasing redline. You can mix and match street cams and street forced induction. It’s up to you can your car to what works best. I would advise against going both race cams and race forced induction as you an unwanted jump in power that can lead to spinning out in higher rpms. I find that about every 400-600lbs of weight needs about 100hp to drift. It’s possible to do it with less but this is a good average to work with if you’re spinning out too much or aren’t getting enough wheel spin.

Drift tuning:

Once again, I am not an expert and drift tuning is different for each person. The purpose of this is to help you find the appropriate settings for your car if you don’t have a clue to what does what.

A good place to start is the racing techniques forum. The reason why I say this is because if you can setup a car to handle neutral (no oversteer or understeer). You can rather force the car to act a particular way, rather than fight and try to counter act the characteristics of the car. Also if you plan to have multiple drift cars by setting them to neutral as a benchmark will allow you to use different cars in your garage in the same manor rather than having to drive a car in a particular style because it handles a certain way. There’s no way to get all your cars in your garage to handle exactly all the same, but it they all were setup to run neutral it’s easier to use the same driving techniques.

I recommend checking out this link: http://forums.forzamotorsport.net/forums/thread/242646.aspx and trying out some of the suspension calculators. Good place to get you started.

Now for the drift specific tuning. Understand that you're forcing the car to oversteer thus the car needs to be setup to understeer. This way the suspension becomes neutral again when you are drifting. It's hard to describe the physics behind it but it has to do with weight distribution and the direction of the power applied to the tires. If you can visualize what areas of the car is being stressed during drifting you can understand what needs to be adjusted in order to get the car to handle smoothly during drifting. Note: This is setting up FR RWD cars. MR/RR RWD is a little bit different but you can do the same tuning to yield the same results but the numbers stated in this guide will vary for MR/RR RWD cars.

Tire pressure: The idea here is have grip while sliding. This can be done by having the front tire pressure higher than the rear. I find that a 40-55 psi in the front works for me. This is creating less resistance and allowing the car to slide somewhat of all 4 tires. Less resistance means a higher corning speed. You might think I'm a little crazy but when you tweak the camber and caster later the tires will get the grip necessary to turn. The rear tire pressure stays in the range of 27-35psi. It depends on how much wheel spin you get. Lower hp cars will be closer to 35 psi where high hp cars will be below 30 psi.

Also note that tire pressures change the way the car can handle dramatically. If your having problem with tire grip/slide on entry and exits play with the tire pressure. If the car has too much power and oversteers while drifting I’ll lower the rear tire pressure. If I want more slide or the rear end to break more I’ll increase the rear tire pressure. Stock front tire pressure creates unnecessary grip that creates feedback in low speed drifting. It also makes oversteer which you might feel like your car is spinning out all the time.

Suspension:
Front camber: Running negative camber in the front should be adjusted so that when you’re in mid drift the outside tire is at 0. Try drifting your car and watching the telemetry. From my experience front camber is somewhere in the range of -1.5 to -3.0. What front camber will do is when you’re drifting and you want more countersteer strength, try increasing the negative camber. If the car jerks when you countersteer, decrease the amount of negative camber. You’ll know what I mean when your car is drifting one way, you let off the throttle or try to steer and your car will suddenly turn in the opposite direction. Too much negative camber and you're going over the point of optimum grip and running too much. Finding the balance is key because you want fluid and smooth drifts.
Rear camber: Normally I run from -0.5 to -1.0. Increasing negative camber can help lose traction to the rear thus making it easier to initiate a drift. If your car has a lot of horsepower and torque and feel that it is hard to control, you might want to run less negative camber to increase grip. I like to adjust my negative camber close to 0 when I’m at or close to the maximum drift angle. That way I get more traction to that outside tire as I’m close to spinning out.

Toe: This affects the cornering ability of the car. With toe out you can make a heavy a** car handle like a ballerina. Positive toe (toe out) helps when turning into a corner. Negative toe (toe in) is to increase stability. Ideally if your car struggles to break loose into a turn add positive toe to the front. If the rear end breaks loose too easily add negative toe to the rear. Generally front toe settings should be around 0.0 to 3.0. Rear toe can range from -0.3 to 0.3.

Caster: Caster and camber work hand in hand. The two effect how much camber is in the front when turning and when weight of the car is distributed to the front wheels. It's the axis at which the wheel turns/pivots. By increasing the caster angle, the axis is titled that causes the inside wheel to create camber on both tires to aid in turning. Higher the caster the more camber your front wheels will have in braking, turning situations, and hitting rumble strips. I prefer to run maximum caster.

Anti-roll bars: Designed to complement spring rates to balance weight transfer from side to side. Front and rear bars work as a ratio to balance weight from side to side. For a RWD setup the ratio should be somewhere from 2:1 and close to 2:1.2. I like to keep the front around 36 and the rear at 19. What anti-roll bars do while drifting is the ability to break the rear end loose on entry but keep the car from washing out. I like the stiff front because while the rear end is sliding the front is driving the car.

Grip driving you have softer settings for these bars, but for drifting I like them hard because there's more torsional stress on the suspension.

Spring rates: Using the forza calculator settings I choose to run softer settings because of the stiff roll bars. Raise spring rates at about 25 lbs each time until it handles to your liking. Front spring rates will contribute to braking and entry while rear spring rates will contribute to acceleration and exit. Front will generally be stiffer for FR and almost balanced or slightly opposite for MR and RR cars. The amount of the spring rates will contribute to the weight of the car lightweight cars are low in the 150 range -/+75 for front and rear. And heavy a** cars in the 3000 range will be around 450 -/+ 100.

Rebound stiffness/Bump stiffness: Dampers work hand in hand with springs. Without dampers nothing is there to control the enegry thats making the spring move up and down. Kinda like a slinky. Rebound is the amount of travel the shock absorber has. Longer stroke = more stable slide, shorter stroke = more skittish slide. If you think about racing coilovers, the more expensive ones allow you to adjust this to be longer to increase stability. Bump is the shaft, that goes in the shock tube, that goes in an out, depending on the setting you can then visualize how much of it you actually want going in, remember that it cant go all the way in, and it cant stick out, because it will become stiff.

If your car is understeering on corner entry, you need to decrease front bump or increase rear rebound. If it is over steering on corner entry, increase front bump or decrease rear rebound.

FR cars the front rebound will be around 10-11 range with the rear rebound from 7-9. adjusting the bump should be within a range equal or less than by 3 of the rebound. MR and RR cars are more balanced because there's less weight transfer due to engine position.

Ride Height: This is something that varies between drivers… Lower ride height means less shock travel and when shocks hit compress to their max, traction to that particular tire is lost. Sometimes you want to lose traction as it aids in getting more slide in a drift. And for particular courses with changes in elevation can make the shocks compress all the way. For the most part I drive with them all the way down and it’s fine, but if you’re going for a drift time attack, watch the telemetry of your replay on that track and adjust the ride height so it doesn’t bottom out. Sometimes prefer to have the rear .1 lower than the front to help out with weight transfer when braking.

Brake balance: Some people like creating bias to either front or rear. Sometimes in the rear to lock them, or in the front to create weight transfer. These figures are different based on each person's driving preference as some people have a tendency to trail-brake compared to those who brake early.

Brake pressure: If drive ABS off then you'll want lower pressure. The higher the pressure the more sensitive you'll have to have to be with the brake trigger. With ABS on higher pressure will allow you to apply the brake bias harder. It really depends on the weight of the car and the front/rear weight distribution. Play with the settings to get your brakes to lock when you want them to.

Downforce: I don’t really mess with this because a lot of my cars don’t have adjustable downforce. It sucks that only the forza aero parts allow adjustability. If you have forza aero parts, turn them all the way down when initially tuning your car. Because downforce can really mask oversteer and understeer problems with the suspension. Downforce helps in mid to high speed cornering. Add more to the front/ less in the rear if you want oversteer. Opposite for increased understeer.

Differential tuning: Accel tuning is set higher for more HP cars. Launch your car, it if pulls to 1 side, (torque steer) increase the accel about 5% until it pulls straight. Some people prefer increasing the accel to 100% I like it right on the border where the car accelerates straight. Why? Because a differential is tuned so that with the right amount of throttle it makes both wheels spin the same. Having it on the borderline will make my car pull straight, and while drifting I can be heavier on the throttle. At 100% you’ll get a lot of wheel spin to one side increasing the likelihood of spinning out. This is tuned to your preference and driving style.

Deaccel works together with brake balance. Increasing the deaccel wit help with creating oversteer when braking or initiating a drift. Start out around 40%, heavier cars and cars that have a front/rear ratio larger than 53% increase this, lighter and more balanced cars decrease this value. Again this is tuned to your preference and driving style. If your car is balanced you can turn this all the way down but I like how deaccel makes it easier to initiate oversteer.

Alternatively you can also run the 1.5 differential which most people find works well.
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