What is the RB26DETT engine?

The RB26DETT is Nissan's 2.6-liter inline-six twin-turbocharged engine used exclusively in the Nissan Skyline GT-R (R32, R33, R34) from 1989 to 2002. It produces a factory-rated 276 hp (actual output is closer to 320-330 hp in stock form due to Japan's gentlemen's agreement cap). The engine is renowned for strong aftermarket support, ability to reliably support 600+ hp with forged internals, and a highly tunable architecture.