A sleeper (US English) or Q-car (British English) is a car that has high performance and an unassuming exterior. Sleeper cars are termed such because their exterior looks little or no different from a standard or economy-class car (or in some cases worse due to seeming neglect on the owners part), but internally they are modified (or are built) to perform at higher levels. The American term comes from how an aggressive animal can seem gentle or perhaps friendly until awoken, while the British derives from the Q-ships used by the Royal Navy. Some cars are equipped this way at the factory to suit the tastes of those who want performance without drama, whether understatedness suits their chosen image or lifestyle, or because they do not wish to attract undue attention of the police. For instance, many high-performance sedans look hardly different from the lower-powered models in the range; for example, the Audi RS4, Acura TL Type-S, Buick Regal GNX, Cadillac CTS-V, Volvo S60R, Chrysler 300C SRT8, Mercury Marauder, Volkswagen Passat W8, 1996 Chevrolet Impala SS, Ford Taurus SHO and the Dodge Charger SRT8, among others. Cars with external badging, or other visual elements that give the impression of high performance, are not true sleeper cars. It is often suggested that the Mercedes-Benz 450SEL 6.9 was the first production 'super-sleeper', with many owners ticking a box on the option list that removed the '450SEL 6.9' badging from the car's trunklid. Without it, the car appears externally extremely similar to any other period Mercedes saloon and belies extreme performance. This trend of overtly powerful saloon cars with subtle body modifications is exemplified by the work of Mercedes-AMG and Brabus on unassuming Mercedes saloons and brings a new and expensive slant to bear on the idea of sleepers, which, until the 450SEL, can be said to have been more owner- than manufacturer- driven. These tuning-shop modifications are also in contrast with actual in-house modification, such as the cars suggested in the paragraph above or the BMW M-series of saloons. Other vehicle owners create sleepers by swapping more powerful engines or other performance modifications like turbochargers, leaving the external appearance exactly the way it came from the factory. Sometimes hints of the car's true nature show if one looks and listens carefully: wider tires, a lower stance, or a different engine tone or exhaust note. Gauges and instrumentation are often kept to a minimum. Some owners go as far as to use weight reduction techniques employed by other performance enthusiasts, such as removing items not fundamental to street racing, such as rear seats, interior trim, spare tire, or even the heater.
In some countries, customized sleeper vehicles (as with other heavily modified street cars) may be considered illegal for road use because the car's level of performance is higher than intended by the vehicle manufacturer; if the owner has focused only on straight-line performance, the existing braking, steering, tires, and suspension systems may have been rendered inadequate. The emissions control system (such as intake and exhaust restrictions or the EGR system) is often bypassed or removed entirely in customized sleeper vehicles. Owners sometimes reduce the evidence that their high-performance car is such by removing characteristic badging and trimmings. Sleeper cars often contain stock body work and wheels found on their less-capable brethren to better blend with other traffic and appear unassuming. Some owners simply like having performance without show, but a more predatory use of the sleeper is in street racing, where it is used to fool an opponent into underestimating a car's performance for the purposes of "hustling". Some have even gone so far as to leave their cars' exteriors banged up and rusting and sometimes even causing additional rusting with the use of battery acid. Resulting vehicles are sometimes known as 'beaters'. It is also occasionally suggested that some British special forces engaged in Iraq use highly-modified but unassuming saloons to avoid attracting attention, in contrast to stereotyped 'shock-and-awe' American mechanized convoys. Sometimes sleepers will be cheaper to insure when compared to an equally fast sports car, but some insurance companies may refuse insurance to owners of heavily modified vehicles. Successfully and intentionally performing this feat may be considered insurance fraud.
See also
- Drag racing
- Hot rod
- Rat rod
- Contrast: Rice burner
