Spring Installation guide for Subaru WRX STi:

9.) Getting everything tightened up:

Lower strut bolts – front (19mm) – 129 ft-lbs
Lower strut bolts – rear (19mm) – 145 ft-lbs

Front brake line (12mm) – 23.6 ft-lb
Front ABS line (12mm) – 24.3 ft-lb

Strut top nuts (12mm) – 14.5 ft-lb
* this isn’t much; don’t overdo it, they can and will snap.*

Strut top center nut (17mm) – 41 ft-lb

The strut top center nuts you can torque when the car is back on the ground. Since your torque wrench doesn’t likely have a pass-through for the Allen wrench, you can use the weight of the car to keep the struts from spinning. In my experience, 41 ft-lbs is pretty close to just cranking it as tight as I can get it by hand with the Allen wrench and pass-through socket.

Note that in the rear; if you put the metal dust covers on before you drop the car, you can’t get to the center nut to torque it. You could just put the 12mm nuts on a few threads, then drop the car, but that could run a slight risk of messing up the threads depending how things line up.

02-07 Subaru WRX/STi Springs:

RCE Racecomp Engineering Yellow Lowering Springs Subaru STI 2004-2007

Swift Sport Springs (Subaru STi 2004-2007) 4F902

Tein SKS66-AUB00 S.Tech Lowering Spring for Subaru Impreza

Tanabe TDF107 DF210 Lowering Spring with Lowering Height 1.3/0.8 for 2005-2007 Subaru Impreza WRX/STI

Subaru 2005 Impreza Impreza WRX STi (with P.C.D: 5×114.3 ) TEIN S-Tech Springs (1.7F/ 1.2R) Part: SKS66-AUB00

TANABE DF210 Lowering Springs Subaru Impreza WRX 02-03

Epic Engineering Lowering Springs Subaru WRX 2004-2007