In this installment of the Project STI, we will be discussing, installing, testing the Whiteline ALK(anti lift kit). This item is used to reduce understeer associated with applying the throttle while cornering as well as improving front end grip in general under braking under acceleration. Anyone who is interested in improving their Subaru's handling should put this item high on their mod list.

How it works
The ALK has been a topic of confusion for most people, including the manufacture, on how it actually works. Many believe that this kit improves handling by reducing the lift and dive tendencies; however it's quite the opposite. From the factory, the STI and many other vehicles have a certain percentage of lift and dive resistance engineered into the suspension geometry to keep the car flatter. These kits modify the anti-lift (and dive) geometry which is where the name for the product is derived.To understand the function we must first look at the forces acting on the vehicle that make it lift or dive under power or braking. Weight transfer from braking or accelerating causes the car move up or down. The degree of this roll is a function of the wheelbase, weight, and the center of gravity. This transfer and roll cannot be altered using an ALK, however it does compensate for the affects of it. The other forces are cause by the torque applied by the brakes and drive train at all four corners on an AWD car. There is no such thing as anti-lift geometry in the front of a RWD vehicle. As the STI accelerates, torque applied by the wheels attempts to pivot the car down to the rear. This lifts the car and pulls the control arm down (applying more pressure on the tires). Factory anti lift geometry reduces this tendency by reducing compliance and therefore reducing grip. The added compliance created with an ALK helps to combat the natural weight transfer caused under these conditions by keeping the tires more firmly planted to the surface.The geometry is altered by lowering the rear mount of the front control arm by 20mm. This brings the geometry from a 6.5% anti lift to 6.1% pro lift condition. Additionally, the caster is increased by .5 degrees. This helps turn in, and also helps to account for any negative decreases in caster cause by the great range of suspension movement that is now allowed. A third advantage of the ALK is harder bushings which reduces play in the suspension. The Whiteline ALK is offered in three variations with the difference being the stiffness of the bushing (Comfort, standard, and race). The standard kit will be adequate for the majority of users who daily drive their car. The race kit can be a little harsh and noisy for the street.

Installation
There are several different variants of this product that do pretty much the same thing with only a slight difference in construction, price, and effect on geometry. For the Project STI, the Whiteline Standard ALK kit was chosen and sourced from Rally Sport Direct. The kit consists of the two new rear mounts for the front control arm, spacers for the subframe, and several washers, bolts, and nuts. Install time is about 1-2 hours and may require air tools and a large breaker bar. Use the instructions as a supplement to the Whiteline instructions.

• First, remove the plastic under tray and side plastics that overlap the subframe (you can partially remove these by only pulling down the front half)
• Remove the front subframe. This is the large metal U-shaped piece that goes underneath both control arms. There are ten large bolts along the sides and two smaller ones at the front. Two of the larger bolts are hidden under a plastic cover that must be removed. There are also two plastic fasteners holding it onto the fender lining.
• Remove the large nut from the back of the control arm at the rear control arm mount on either side
• Remove the two bolts holding the mounts on for each side. These are very tight and may require air tools.
• Remove the mounts. You will need to pry down the control arm to do this. Retain the inner larger washer from the stock mount.
• Clean and grease the end of the control arm as well as all surfaces of the new Whiteline bushing
• Reassemble with the correct mount putting in the OEM large black washer first, then the ALK mount, then they large supplied washer, and finally the supplied large nut. Tighten down the end nut as much as possible. This will aid in lining up the holes on the mount.
• Bolt in the mounts.
• Reinstall the subframe making sure to insert all the spacers as directed. Easiest method is to thread the front two small bolts and then work your way back, and thread each bolt only a few turns before tightening down the entire piece.
• Check tightness and replace plastics.
• An alignment should be done soon after install, however consider adding camber bolts or plates to increase negative camber.

Testing
Initially, there wasn't a highly noticeable difference in the way the car drives. No noticeable increase in noise or harshness.  Just a slight hint of more repsonsive steering thanks to the increased caster.  However when you exit the first hard corner, the benefits are instantly apparent. The easiest way to see this is to put the car into a tight low to mid speed corner and ram the throttle after the apex. Previously, there was an obvious tendency from the car to push, sometimes heavily, to the outside. As long as you don't totally butcher the corner, this seems to have been nicely cleaned up and now exits the corner in a civilized neutral manner. Turn in and response has also been somewhat enhanced thanks to the increased caster and tighter polyurethane bushings. On the track, the changes are even more noticeable. We were able to maintain a cleaner faster line and apply the throttle earlier and harder, increasing exit speeds. This together with the Whiteline steering rack bushings removed the majority of the negative attributes the stock STI had. For the owner that does not wish to go much further than this point, camber bolts or plates would be the next handling modification to round out the package. Giving the vehicle maybe an extra one degree of negative camber would also help to eliminate understeer and dramatically improve turn in without excessive tire wear. 

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