Sleepers - ordinary looking performance cars.

"A Wolf in Sloths clothing."

What are Sleepers or "Q" cars?

A car that looks innocent on the outside but underneath it is a real racer. There are many cars out there that have a great deal of performance and little in the way of image.

Take a Volvo T5 turbo – stonking performance from an innocent looking slab of metal. There are a couple of ways to get a sleeper – take a boring car and soup up the engine and handling – keeping the exhaust pipe narrow and venting the real exhaust from a hidden vent.

Or you could take a high performance car and remove the high performance badges, bodykits and accessories making it look like a regular street car.

sleeper exhaust

You would also avoid the induction kits that add a roar to the engine and enclose the induction kit within an insulated box with a cold feed pipe. Often a high flow filter in the standard air box will provide a suitable performance gain without the tell tale roar.

A sleeper will always be apparent when the engine starts up to a well trained ear – it will have that familiar tuner roar & raspy zzzzz and the revs rise and fall quickly indicating the presence of a light weight flywheel.

A way to spot a well tuned and balanced engine is to listen to the exhaust note – it will purr rhythmically especially when the engine is up to temperature.

An intermittent burble especially after revving the engine is quite normal and indicates the presence of a fast cam profile. On the road a sleeper will show a clean pair of exhausts to most cars around.

Despite the lack of image you still have the performance and can earn respect and teach manners to others on the track.

The other way of getting a sleeper is get a high performance car such as an Audi RS6 and switch the badging & body kit for that of a standard diesel model although you would really want to keep the wide wheels to control all of that power – wide mud flaps can help to hide the true wheel width from anyone following.

Nissan sleeper

There’s something cool about having a sleeper – the kids in their plastic covered shopping cars wont try to race you away at the lights or even expect you to leave them standing if they try to roar away. The car is obviously not attractive to thieves or the local law enforcement agencies.

A friend of mine complains that he is always being pulled over by the police and subjected to document checks when he drives his car around which shouts ‘I’m a racer’.

Whereas in a sleeper you are ignored or dismissed. Despite the lack of image you still have the performance and can earn respect and teach manners to others on the track.

One of the reasons the Skylines are so popular is their relatively normal executive image and absolutely blistering performance. Most people wouldn't be able to tell the turbo from the 1.8 saloon unless they know what the trim badges and subtle body modification are.

Old cars often surprise people as sleepers – imaging a mk1 escort upgraded with a 2.0 320bhp cosworth engine which is a fairly popular conversion up against a showroom standard ‘sports car’. The beauty of an old car is that people forget what was standard and just assume that old = slow. Older cars also have less stringent emissions test and don’t require a catalyst so you can get away with stonking modifications.

Why not join us in our forum and see what sleeper projects our members have - you'll find everything from Old Skool cars to tuned Cosworths, Saabs and Volvo T5's.

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One Response to “Sleepers – tuning ordinary looking cars”

  1. Bob James says:

    I am definitely into the sleeper style nowadays rather than the obviously modified look i preferred when i was younger.

    The two best cars I’ve found for the pass by unnoticed effect were a blue mk3 Cavalier 1.8 LS 5 door around 10 years ago and a silver Avensis nowadays which is what i happen to be running about in. They are almost completely invisible to police cars it seems like magic somehow. Makes me grin to see some winged, body kitted beamer or Honda V-tec sitting in a layby with the blue lights parked up behind it and a gang of lads hanging around for the driver to be let out the back lol

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