Drifting
refers either to a driving
technique, or to a sport based on the technique;
this article deals primarily with the sport. When
the rear slip angle is greater than the front slip
angle, and the front wheels are pointed in the
opposite direction to the turn (e.g. car is turning
left, wheels are pointed right), and the driver is
controlling this, the car is drifting.
Drift cars are usually light to moderate weight,
rear-wheel-drive passenger cars. In Japan and
worldwide, the most common drift machines are the
Nissan Silvia/180SX, Toyota AE86, Mazda RX-7, Nissan
A31 Cefiro, Nissan C33 Laurel, Nissan Skyline (RWD
versions), Nissan Z-car, Toyota Altezza, Toyota MZ20
Soarer, Honda S2000, and Mazda Miata. US drift
competitions feature local versions of those cars
(such as the Nissan 240SX and Toyota Corolla GT-S)
as well as American performance cars such as the
Ford Mustang, Dodge Viper, and Pontiac GTO. Drifters
in other countries often use local favorites, such
as the early Ford Escort (UK and Ireland), BMW 3
Series (other parts of Europe), Porsche, early Opel
cars, or Volvo 700 series (Sweden).
Drifting techniques
The basic driving techniques used in drifting are
constant, though each car and driver will employ
some subset of these techniques. They include:
Beginner Techniques
These techniques don't use weight transition, so are
typically the first thing the novice drifter learns.
However they are still used by the most experienced
drifters, and require skill to execute properly.
* Hand-brake or Emergency brake drift - While the
clutch is depressed, the hand-brake is pulled to
induce rear traction loss. As soon as traction is
lost, the driver releases the clutch, depresses the
accelerator, and countersteers. This is generally
the main technique to attempt to drift a FWD car
(clutch unnecessary). Also, this technique is used
heavily in drift competitions to drift large
corners, or to trim the car's line mid-drift.
* Power oversteer or Powerslide - This drift is
performed when entering a corner at full throttle to
produce heavy oversteer through the turn. The excess
power causes the drive wheels to lose traction in a
RWD or AWD car. This is the most typical drifting
technique for all-wheel drive cars.
* Shift lock - Initiated by downshifting (usually
from third to second or fourth to third, and using a
very fast shift) instead of braking, without
rev-matching, causing the drive wheels to lock
momentarily. Helpful for very tight corners,
allowing the driver to approach the corner at a
slower speed and lower revs, while allowing quick
acceleration when exiting the corner. This technique
can be very damaging to the engine if mis-used as
the ECU is unable to rev limit when the engine is
oversped by the rear wheels. Premature downshifters
are called "Rod Stretchers".
* Clutch kick - This is done by "kicking" the clutch
(pushing in, then out, usually more than one time in
a drift for adjustment in a very fast manner) to
send a shock through the powertrain, upsetting the
car's balance. This causes the rear wheels to slip.
Weight Transition Techniques
* Braking Drift - This drift is performed by braking
into a corner, so that the car can transfer weight
to the front. This is immediately followed by
throttle in a RWD car causes the rear wheels to lose
traction. FWD cars can also use this technique as it
does not depend on the rear wheels being driven.
* Inertia (Feint) drift, or Scandinavian flick -
This is done by transferring the weight of car
towards the outside of a turn by first turning away
from the turn and then quickly turning back using
the inertia of the rear of the car to swing into to
the desired drifting line. Sometimes the hand-brake
will be applied while transferring the weight of the
car towards the outside to lock the rear wheels and
help the rear swing outwards. This type of drifting
causes the car to accelerate faster afterwards,
because of momentum built up while drifting.
* Kansei, Lift off, or Taking In - By letting off
the accelerator while cornering at very high speeds,
cars with relatively neutral handling will begin to
slide, simply from the weight transfer resulting
from engine braking. The drift is controlled
afterwards by steering inputs from the driver and
light pedal work, similar to the Braking drift.
Other Techniques
* Dirt drop - This is done by dropping the rear
tires off the sealed road onto dirt, or whatever
low-grip surface borders the road, to maintain or
gain drift angle. Also colloquially called "Dirt
Turbo". [10]
* Choku-Dori - This is done by swaying the car's
weight back and forth on straightaways, using
countersteer and throttle to maintain a large angle.
This is a show maneuver that usually involves many
cars following the same line.
Drift 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
bōsōzoku) 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.
Cockpit
Because 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 castor 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
S13 Silvia bay with typical drift mods -
including oil cooler, front mount intercooler (pipes
only visible), remote oil filter mount, strut brace,
camber strut tops, high mount turbo, glove over
brake master cylinder.
S13 Silvia bay with typical drift mods - including
oil cooler, front mount intercooler (pipes only
visible), remote oil filter mount, strut brace,
camber strut tops, high mount turbo, glove over
brake master cylinder.
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
Cleaning up severed bars during Drift meet.
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
S13 Silvia - tire stretched over a wide rim,
increasing sidewall rigidity. The rim has a high
positive offset to increase track.
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 Kumho.
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 racing teams at the
moment. |
|
