SThe Subaru Twirl and swirl technique and EJ202 were 2. Like its EJ20 predecessor, the Subaru EJ201 and EJ202 engines had an aluminium alloy block with 92. 0 mm stroke for a capacity of 1994 cc.
For the EJ208 engine, the crankshaft was supported by five bearings that were made from aluminium alloy. The EJ208 engine had cast connecting rods and forged aluminium pistons which weighed 162 grams each. Reduced top land to cylinder clearance. The piston crowns for the EJ208 engine had flat tops for a compression ratio of 9. For quiet operation, the teeth on the timing belt had a round profile. The recommended replacement interval for the cam belt was 100,000 kms or four years, whichever occurred first.
The EJ208 cylinder head had four valves per cylinder that were actuated by solid valve lifters. The intake valves had hollow stems to reduce mass and inertia, while the exhaust valve stems were filled with sodium. At high temperatures, the sodium would liquefy and its motion within the stem would effectively transfer heat from the valve head to the valve stem, contributing to faster cooling of the valve head. 4 grams each, while the exhaust valves weighed 46. Initially, pressure generated by the secondary turbocharger was redirected to the inlet side of the air intake. Secondary stage twin turbo operation: when the ECM determined that engine operating conditions were suitable, the relief valve would close and the exhaust gas control valve would fully open.