Nissan released the Datsun 280Z model for the U.S. market in the 1975 model year. In a further effort to keep the S30 models sporting in the face of increasingly stringent U.S. emission and safety requirements, engine size was again increased, this time to 2.8 L. The L26 engine was bored out .2 L to create the L28, and a reliable Bosch L-Jetronic fuel injection system was added.
1975 and 1976 models continued to be fitted with the U.S. federally required 5 mph (8.0 km/h) impact absorbing bumper that were introduced for the mid-1974 model year of the 260Z. These bumpers were smooth surfaced, and blended into smooth black rubber extensions as they met the body of the car. 1977 and 1978 models received bumpers with recessed channels added to the faces of the bumpers themselves, that blended into corrugated or accordion style black rubber extension trim. Also new for the 1977 model year, 280Zs no longer received the full size spare tire, and instead had a “space saver” spare and a larger fuel tank. This resulted in a raised rear deck area made of fiberboard, reducing cargo space. In 1977–78 an optional 5-speed manual transmission was available alongside the 4-speed manual and the 3-speed automatic options. It included a “5-speed” emblem on the left bottom edge of the rear hatch. 1977 also saw an update from the charcoal painted hubcap style (with a chrome Z floating in the amber center emblems) to a hubcap that resembled an alloy wheel, bearing a center cap with a chrome Z floating in a black circle.Discover more on Wikipedia