Introducing the PERRIN Performance P.S.R.S. for 2011 STI.
Along with the suspension changes on the 2011 STI's came new front lower control arms that now use a larger rear bushing.
To keep the tradition of the popular PERRIN Performance P.S.R.S. going we have developed the part to fit the new control arms with larger units.
What is the PSRS?
P.S.R.S stands for Positive Steering Response System and simply replaces the front control arm, rear bushings. This OEM bushings are 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. Eliminating the OEM super soft bushing provides significant improvement in how the car steers during hard cornering and even in a straight line.
OEM Bushings - Bad
Under braking and acceleration, the OEM bushing can flex enough for your wheel to move back and forth .500"! This deflection of the wheel causes drastic toe in and toe out changes under braking. The toe changes will cause steering wandering and an altered tire contact patch. When accelerating, this OEM bushing causes unwanted wheel hop and the car will want to follow the ruts in the road.
PERRIN PSRS - Good
After the PERRIN PSRS is installed, under braking the wheel will have zero deflection. Since there is no way for toe changes to occur, the steering feedback issues and wandering under braking disappears. Under acceleration the car will have far less tendency to follow the ruts in the road, wheel hop will be eliminated and in turn the car will have more front end traction.
The bushing in the PSRS is purposely offset from centerline(Except Zero Caster Part). This adds almost 0.6 degrees of caster to the front suspension. Caster is the angle on which the steering knuckle rotates. Adding caster makes the car turn in faster by providing a larger contact patch as the wheels turn on the steering axis.
A byproduct of the added caster is an anti-lift effect. The PSRS reduces the amount of front end lift during acceleration. During hard acceleration a cars weight shift to the rear, lifting the front wheels and reducing front end traction. The PSRS limits the weight shift, increasing front end traction. This is most notable during hard acceleration while exiting a turn.
Need more info? Just search here on IWSTI and other forum boards for feedback from other PERRIN P.S.R.S. users.
All this coolness for only $239.99
Most of our coupon codes will work on this item to save you some money.
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