Cylinder 4 cooling has long been a known issue on the EJ Family of Subaru engines. The nature of the water passageways around this area means a lack of cooling can lead to an increase in the temperatures around this cylinder.
RCM's simple solution to this problem lies in our easy to fit complete kit. Billet fittings are banded in place on our custom 90 degree Samco silicon hose, which you simply fit into the unused port at the back of the block at cylinder 4's location. This is then tee'd into the water matrix pipe directly above using the supplied HiGrip stainless steel fittings. The billet barb fitting is of the correct diameter to allow the right flow rate around cylinder 4 to cool without over cooling, and the 90 degree pre-formed Samco hose ensures that this flow is maintained without disturbance from potential kinks in the pipework.