When the Formula One team McLaren decided to build the ultimate road-going sports car, it knew that it would need a very special engine, something massively powerful and hugely strong. And it couldn't be turbocharged: the ultimate sports car couldn't suffer from turbo lag.

Where do you get an engine like that? The answer was BMW. In fact it already had the engine — well, half of it. The idea? Bolt two M3 power plants together and you have a 6 litre V12 with 627bhp. Perfect.

So if you fancy a car with arguably the world's most incredible engine, you have a choice: buy a McLaren F1, £634,000 in 1994, and own all 12 glorious cylinders, or buy a used BMW M3 Evolution for Ï12,000 and get half that stupendous motor.

Right, so you want to know about the BMW? The M3 Evolution was introduced in March 1996 in three guises: saloon, coupé and convertible. It differed from the previous M3 by having a larger engine, up from 3 to 3.2 litres, and a manual gearbox with six instead of five gears. The larger engine boosted power by nearly 40bhp making it BMW's fastest car.

The M3 saloon stayed in production for less than two years, whereas the prettier coupé and cabriolet continued until late 1999. During that time little changed apart from the introduction of the semi-automatic sequential manual gearbox (SMG) in March 1998. Purists dislike the slightly jerky SMG but if you spend much time driving in town it's worth a look.

Mechanically these BMWs are strong but they attract enthusiastic drivers so wear can be heavy. If the car clunks when pulling away it's usually the propshaft bush joint or rear subframe bushes. Both can be put right for a few hundred pounds but it tells you something about the owner's attitude to maintenance and it might be better to walk away.

Many M3s bear personalised registration numbers so run an HPI check on the car to validate its history. Service intervals vary according to use but be suspicious of gaps of more than 12 months or 12,000 miles. A false service history is a potential problem with many high-performance or specialist cars so be sure you see original invoices, too.

Interiors last well and should be tight and rattle-free, though the driver's seat can wear and is difficult and expensive to repair

Despite costing £40,000 new, air-conditioning was an option before September 1998. Expect to pay up to £1,000 more for cars with electric front seats and air-con. Metallics are the most desirable colours.

Insurance is group 20, so it's worth getting a few quotes, and servicing through a main dealer can be costly. If your budget is tight you can save money by using a non-franchised specialist but, even at £140 each, don't cut corners on tyres: with over 320bhp and no traction control you want all the grip you can buy. Fuel economy depends entirely on driving style but expect the mid-20s on a run.

Despite the arrival of a new M3 with even more power in 2001, the old Evo models are still in demand. Check BMW-approved used dealers for late, low-mileage cars. For older examples try the classifieds and specialist publications.

VITAL STATISTICS
Model BMW M3 Evolution coupé
Engine Six cylinders, 3201cc
Power 321bhp
Transmission Six-speed manual
Fuel 25.7mpg (combined)
Acceleration 0 to 62mph: 5.4sec
Top speed 155mph

CHECK OUT
Air-con Not standard until late-1998 but a must-have option
Upholstery Edge of driver's seat prone to wear
Alarm Insurance company may insist on specific security system
Seats Electric front seats not standard but a good option to have
Colours Metallic finish is best, white is worth £1,000 less
Spare wheel Always ensure the spare wheel and tyre are there and match the others
Chassis Rear subframe bushes prone to wear, and substandard items mean an MoT failure
Tyres Check brand and condition of tyres carefully: mismatched tyres are a sign an owner is running the car on a budget and shortcuts can spell disaster
Wheels 17in alloys prone to scuffs and major damage cannot be refurbished
Spoiler Deep front air dam vulnerable to stone chips and damage
Engines Pretty strong but cars with over 80,000 miles can have slight tappet rattle when cold
History Check the invoices as well as service stamps
The one to buy BMW M3 Evolution coupé manual. 1998 S, 50,000 miles with full BMW service history. Pay £16,500 from a BMW main dealer or £15,000 privately

VALUES BMW M3 Evolution coupé
Mileage 30,000
1997 R Trade £14,050. Retail £16,295
1998 S Trade £15,800. Retail £18,095
1999 T Trade £16,600. Retail £19,095

Mileage 50,000
1997 R Trade £12,750. Retail £14,995
1998 S Trade £14,250. Retail ££16,500
1999 T Trade £14,950. Retail £17,450 £15,295

Mileage 90,000
1997 R Trade £10,300. Retail £12,250
1998 S Trade £11,950. Retail £14,195
1999 T Trade £12,800. Retail £15,295


Add £500 for cars fitted with SMG gearbox. Saloons fetch £500 less than equivalent coupé, convertibles fetch £2,000 more than equivalent coupés. Source: estimates based on confidential CAP black book prices. 'Trade' is what a dealer would pay to buy your car; 'retail' is what you would pay a dealer