Lexus: The second letter in any Lexus car’s name indicates the body style. An S is a sedan, an X is a sport/utility vehicle and a C is a convertible. The 3-digit number is based on the engine size in liters. So the LS 430 has a 4.3 liter engine, and a GS 300 has a 3.0 liter engine. The first letter in a Lexus name indicates the relative size and cost of the car. The higher in the alphabet the letter is, the higher the price. Except for the R SUVs, they are actually the least expensive Lexus SUVs.