What does the letter i mean in 525i?

Answer 1

BMWs follow a certain nomenclature in the naming of their vehicles; usually a 3 digit number is followed by 1 or 2 letters. The first number represents the series number. The next two numbers traditionally represent the engine displacement in cubic centimeters divided by 100. The system of letters can be used in combination, and is as follows: i = fuel-injected d = diesel† h = hydrogen g = compressed natural gas/CNG e = eta (efficient economy, from the Greek letter 'η') x = BMW xDrive all wheel drive L = long wheelbase C = coupe c = cabriolet (convertible) T = touring (wagon/estate) t = hatchback s = sport†† † historic nomenclature indicating "td" refers to "Turbo Diesel", not a diesel hatchback or touring model (524td, 525td) †† typically includes sport seats, spoiler, aerodynamic body kit, upgraded wheels, etc. For example, a BMW 760Li is a fuel-injected 7 Series with a long wheel base and 6.0 liters of displacement. However, there are exceptions.[18] The 2007 BMW 328i is a 3 Series that has a 3.0 liter engine. The 2007 BMW 335i also has a 3.0 liter engine; however it is twin-turbocharged, which is not identified by the nomenclature. The 'M' - for Motorsport - identifies the vehicle as a high-performance model of a particular series (e.g. M3, M5, M6, etc). For example, the M6 is the highest performing vehicle in the 6 Series lineup. Although 'M' cars should be separated into their respective series platforms, it is very common to see 'M' cars grouped together as its own series. When 'L' supersedes the series number (e.g. L6, L7, etc) it identifies the vehicle as a special luxury variant, featuring extended leather and special interior appointments. The L7 is based on the E23 and E38, and the L6 is based on the E24. When 'X' is capitalized and supersedes the series number (e.g. X3, X5, etc.) it identifies the vehicle as one of BMW's Sports Activity Vehicles (SAV), featuring BMW's xDrive. The 'Z' identifies the vehicle as a two seat roadster (e.g. Z1, Z3, Z4, etc). 'M' variants of 'Z' models have the 'M' as a suffix or prefix, depending on country of sale (e.g. 'Z4 M' is 'M Roadster' in Canada). Both X & Z vehicles will have 'i' or 'si' following the engine displacement number (denoted in liters). The 'si' (e.g. X3 3.0si) identifies the vehicle as being equipped with the 'sport package' & is 'fuel-injected'. X & Z vehicles only denoting 'i' (e.g. X3 3.0i) identifies the vehicle as 'fuel-injected' and no sport package.