GrimmSpeed 08+ WRX/STi AOS - Manual (Page 3)

3. Remove BOV mounting bolts, remove IC mounting bolt, and loosen intercooler outlet hose
clamp. Remove intercooler.
4. Starting on the driver's side of the engine bay, locate cylinder head crossover tube and pull
rubber hose off of crossover tube.
5. Cut 2.5" of 5/8" ID hose (arrow 1 below) and push onto crossover tube. Push 5/8" to 1/2"
hose connector into the 2.5” of 5/8” hose. Push 1/2" hose (arrow 2 below) into other end of
the connector and then run the hose to the center port on the AOS, cut to length. We find that
using a small amount of water on the connector aids in pushing the hose on the plastic
connectors. Push 1/2” hose onto the AOS center fitting.
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