For: 02-07 Impreza WRX and STi
Get the most from steering input with the addition of our PSRS system. Our system increases steering response in corners by adding additional caster angle, straight line performance by preventing lift when accelerating, and installs easily by eliminating the squishy factory rubber mount.. The increased width of plus size wheels adds enough leverage over the factory rubber mounts to literally pull the car side to side, even on slightly uneven pavement. This is extremely unnerving and can be completely eliminated with our PSRS system. Impreza owners that want the increased caster angle but want more compliance in the ride can use the optional Urethane Bushing Set. Available for Impreza, WRX, STi and Legacy.
What is the PSRS?
These kits are also known as the ALK or Anti-Lift-Kit. The anti-lift part of the kit is a very small feature compared to the benifits of the solid type connection the PSRS makes. Eliminating the OEM super soft bushing provides significant improvement in how the car steers during hard cornering and even in a straight line. So P.S.R.S stands forPositive Steering Response System. The PSRS replaces the front control arm, rear bushing. This OEM bushing is designed to be extra compliant to reduce NVH, and make the ride more comfortable. The compliancy of this bushing is not something a performance oriented driver is looking for.
OEM Bushings Installed
Under braking, this OEM bushing has enough flex in it to cause the wheel to move back and forth .500"! This deflection of the wheel causes drastic toe in and toe out changes under braking. These toe changes will cause steering input changes, cause the tires contact patch to change, and even wondering.
When accelerating, this OEM bushing causes unwanted wheel hop, and again toe in and toe out changes. During acceleration, the car will want to follow the ruts in the road, as the bushing flexes back and forth. This is one of the most noticeable changes.
PERRIN PSRS Installed
Under Braking, after the PERRIN PSRS is installed, the wheel will not move front to back period! Since there is no way for toe changes to occur, the steering feedback issues, and wondering under braking all goes away!
Under Acceleration, after the PERRIN PSRS in installed, wheel hop disappears, the car will have far less tendency to follow the ruts in the road, and in turn the car will have more front end traction.
Besides removing all the unwanted flex of the OEM bushing, our PSRS has an offset to where the bushing is mounted. This allows the installer to add almost 2 degrees of caster to the front suspension. Caster is the angle at which the steering knuckle rotates on. Adding caster makes the car turn in faster by providing a larger contact patch as the wheels turn on the steering axis. Think of it like camber for your steering!
One of the byproducts with how we add caster is the ability to add some Anti-lift to the front end. This reduces the amount of front end lift during acceleration. The benefit to Anti-Lift is it keeps the balance of the car in check. During hard acceleration, Soft springs, and shocks makes the cars weight shift to the back. This in turn removes weight from the front that keeps the tires planted to the ground. Which is a very important thing when trying to keep tires planted firmly on the ground while accelerating out of corners.
Urethane Bushing Upgrade
For those wanting something in between the rock solid connection, and the super soft OEM Bushings, the Urethane Bushing upgrade is a great alternative. These are simple replacements for the Delrin Bushing we normally supply. They provide a slightly softer ride compared to the Derin, and transmit slightly less noise through the chassis.
Important Shipping NOTICE: Posted shipping cost ONLY applies for lower 48 states. Shipping to HI/PR/AK/VI/GU may cost more. Please contact us before you place any order. Thank you.