Subaru is known far and wide for its boxer engines. ... the only engine layout the marque ... too. Instead of just a single-cylinder head topped with one intake and one exhaust manifold, you've ...

With a log-style or compact OE-style, unequal-length runner exhaust manifold like you'll find on SR20DET or USDM STI engines, the pulse from one cylinder can interfere with subsequent exhaust gas ...