• ’04 - ’05 oil pump pickup (Subaru PN 15049AA070) ... We used thread locker on the oil pan bolts as a precaution to ensure they won’t come loose from engine vibration. 14.

To produce 395 hp and 400 lb-ft of torque, Cosworth fits the STI’s 2.5-liter flat-four with strengthened pistons, rods, head studs, gaskets, and a high-pressure oil pump. They bolt up a larger ...