Drifting Performance Tuning

Drive train
A proper mechanical limited slip differential (LSD) is essential for drifting. Open diffs and viscous diffs cannot be controlled during a sustained slide. All other modifications are secondary to the LSD. Popular drift LSDs include OS Giken, KAAZ, & Cusco. The most popular form of LSD for drifting is the clutch type, in "2-way" form; this is preferred for its consistent and aggressive lockup behavior under all conditions (acceleration and deceleration). Some drift cars use a spool "differential", which actually has no differential action at all, the wheels are locked to each other. Budget drifters also use the welded differential, where the side gears are welded to give the same effect. This makes the car very easy to slide at high speed, but difficult to park, and is hard on the driveline. Torsen (available on cars such as S15, FD3S, MX5, JZA8x) diffs are adequate, but not generally available aftermarket. The clutches on drift cars tend to be very tough ceramic brass button or multiple-plate varieties, for durability, as well as to allow rapid "clutch kick" techniques to upset the balance of the car. Gearbox and engine mounts are often replaced with urethane mounts, and dampers added, to control the violent motion of the engine/gearbox under these conditions. Gearsets may be replaced with closer ratios to keep the engine in the power band. (Japanese drifters confuse the "L" and call these "cross-mission".) These may be coarser dog engagement straight cut gears instead of synchronised helical gears, for durability and faster shifting at the expense of noise and refinement. Wealthier drifters may use sequential gearboxes or sequential adapters to make gear selection easier/faster.

Suspension
The suspension in a drift car tends to have very high spring and damper rates. Sway bars are upgraded, particularly on the rear. Caster is often increased to improve the car's controllability during a slide. Most cars use an integrated coilover/shock (MacPherson strut) combination. This type of suspension allows the ride height to be adjusted independently of the suspension travel. There is no perfect height setting or spring/shock combo for any car, but each driver will have their own personal preference. Many suspension manufacturers offer suspension tuned specifically for drifting, allowing many people to enter the sport competitively.Bushings can be upgraded with urethane parts. Most Nissan vehicles have a floating rear subframe which is usually fixed in position with billet aluminium or urethane "drift pineapples", to prevent the frame moving during drift. One suspension tuning method, still popular in Japan, is known as "Demon Camber". It involves setting the suspension with extreme negative camber in the front to reduce slide. Negative camber on the rear would only induce understeer, making the car more difficult to drift. The front of the car having better grip and less tendency to slide, it is easier to swing the rear of the car around to get a good drift angle. However stability, grip, and overall ability to control the car are compromised. It has thus fallen out of favor as a serious performance-minded suspension setup. However, many cars built for show (such as those driven by bosozoku) still use this style of suspension setup for its aggressive look. A few degrees of toe-out on the rear wheels in some vehicles (leading edges angled outward) can improve turn-in, and make setting up a drift a little easier. Generally drifting consumes tires rapidly and multiple sets may be necessary for a single professional event.

CockpitBecause of the large sideways forces, the driver must be retained firmly by a bucket seat, and preferably five point harness. This allows the hands to merely turn the wheel, as opposed to bracing oneself against the wheel. The steering wheel should be relatively small, dished, and perfectly round, so that it can be released and allowed to spin through the hands as the caster returns the front wheels to center. The locking knob on the hand brake is usually replaced with a spin turn knob, this stops the hand brake locking on when pulled. Some drivers move the hand brake location or add an extra hydraulic hand brake actuator for greater braking force.

Engine
Engine power does not need to be high, and in fact if a car has too much power, it can be very hard to handle during a drift. Each driver has their own preference, and drift cars can be found with anything from 100bhp (74kW) to 1000bhp (745kW). Typically, engine tuning is oriented towards achieving linear response rather than maximum power output. Engines also must be equipped with upgraded cooling systems. Not only are the engines pushed very hard, creating lots of heat, but being driven at an angle reduces the airflow through the radiator. For turbocharged engines, intercooler efficiency is similarly reduced. Oil coolers are almost essential. V-mounting the intercooler and radiator improves flow through these components, and keep the expensive intercooler out of harm's way in the inevitable offs.

Steering
With increased steering angle it is possible to achieve greater angle with the vehicle, it will also aid in spin recovery. This is often done with spacers on the steering rack, custom steering racks, custom tierod ends, or machining the spindles. Increased steering angle often requires other modifications as at some point the tire or wheel will come in contact with other suspension pieces or the inner/outer fenders.

Body
Chassis preparation is similar to a road racing car. Roll cages are sometimes employed for safety, and to improve the torsional rigidity of the car's frame, but are compulsory in events that involves the 2+ cars tsuiou runs in the event of a side collision. Front and rear strut tower braces, B-pillar braces, lower arm braces, and master cylinder braces are all used to stiffen the chassis. The interior is stripped of extraneous seating, trim, carpet, sound deadening; anything that is not essential is removed to reduce weight. Body kits are usually attached with cable ties. When the body kit meets the wall or curb, the cable ties snap, releasing the part, as opposed to breaking it. As drift cars are pushed faster, aerodynamic tuning becomes more important as well. Rear spoilers and wings usually are useful only in large, open tracks where the cars develop enough speed to create a need for more downforce. Wheel arches are often rolled or flared to allow the fitment of larger tires. Airflow to the engine is critical, so the hood is often vented.

Tires
The cars quite often have different tires on the front and back, and the owner may have quite a few sets. This is because a single afternoon of drifting can destroy a new set of tires. As a rule, good tires go on the front for good steering. On the back, hard-compound tires are used, quite often second-hand ones tend to end up in a cloud of smoke. 15" wheels are common on the rear, as 15" tires are cheap. As a driver gets better, they will most likely want to upgrade the tires used in the rear for a higher grip compound. Although cheap/hard tires are fun purely for their slipperiness and ease of drifting, they quickly become a hazard for high-speed drifts. More advanced drivers require the most grip possible from all 4 tires. Competitive drifters often run DOT approved tires closer to racing tires, which is permitted, with the exception of some major championships including D1GP which only permits commercially available tires that are approved by them. The grip is required for control, speed, and a fast snap on the initial entry. Some companies have started to create tires with special effects for drifting. One such company is Kuhmo. They recently released tires designed especially for the drifting crowd. These new tires produce colored smoke instead of regular grey smoke when drifted. However these tires are generally not available to the public, and only to drift teams at the moment.