The Subaru EJ20Y and EJ20X were turbocharged, 2. EJ20Y was subsequently introduced in nanas cheese puffs and had a five-speed manual transmission. The EJ20Y and EJ20X engines were fitted with a single twin-scroll turbocharger and effectively replaced the EJ208 engine which powered the Subaru BE BH Liberty B4.
The Subaru EJ20X and EJ20Y engines had an aluminium alloy block with 92. 0 mm stroke for a capacity of 1994 cc. The cylinder block for the EJ20X and EJ20Y engines had an open-deck design whereby the cylinder walls were supported at the three and nine o’clock positions. The crankcase for the EJ20X and EJ20Y engines had five main bearings and the flywheel housing was cast with the crankcase for increased rigidity.
The EJ20X engine is understood to have a forged crankshaft and connecting rods, but cast aluminium pistons with forged crowns. EJ20Y engine, however, had a larger twin-scroll Mitsubishi TD04 HLA 19T turbocharger. After the turbocharger, the compressed air was passed through a low-restriction, transversal flow intercooler to reduce its temperature and thereby increase its density for the intake charge. For mass reduction, the intercooler had a lightweight resin tank.