BMW M3 CSL review: Retro Road TestThe BMW M3 CSL sounds like nothing else I’ve driven. Its baritone blare builds to a widescreen, DTM-racer wail as air is sucked through its carbon manifold then spat out through quad exhausts. It gives me goosebumps just thinking about it.

Soundtrack aside, there’s little to distinguish the Coupe Sports Leichtbau from a standard E46 M3. Only the cognoscenti will spot the bespoke 19-inch alloys and subtle lip spoiler. But this is no badge-engineered special edition: BMW tuned the engine to 360hp, fitted a quicker steering rack, stiffened the chassis, beefed-up the brakes and stripped out 110kg of weight.

Does that make a used CSL worth five times the value of an equivalent M3? That’s what I’m here to find out.

This immaculate BMW M3 CSL is offered at Hexagon Classics for £69,995. More details at hexagonclassics.com

What are its rivals?BMW M3 CSL review: Retro Road Test

The CSL’s closest rival is perhaps the Porsche 911 GT3. Both have a track-focused ethos and are fully-paid-up modern classics. The 996 (1999-2005) and 997 (2006-2011) GT3 cost similar money to a CSL: £60k upwards. However, hardcore GT3 RS versions stray well into six figures.

Prefer a sledgehammer to a scalpel? The Mercedes CLK63 AMG Black is available from £70k, while early examples of Nissan’s formidable GT-R are less than £40k. And don’t forget Audi’s 381hp RS4 Avant – yours from just £13k.

What engine does it use?BMW M3 CSL review: Retro Road Test

Cloaked in carbon and squeezed beneath a strut brace, the CSL’s 3.2-litre six is something quite special. Power is upped from 343hp to 360hp at a heady 7,900rpm, with a modest 273 lb ft of torque at 4,900rpm. Yes, this engine needs – no, demands – to be worked hard.

Find a suitable Autobahn and the über-M3 will hit 62mph in 4.7 seconds (0.4 seconds quicker than standard) and a top speed of 161mph.

Controversially, the CSL was never offered with a manual gearbox. All cars had a quicker-shifting version of BMW’s SMG semi-automatic, which allows sequential manual changes via the lever or steering wheel paddles.

What’s it like to drive?BMW M3 CSL review: Retro Road Test

The BMW M3 is perhaps the ultimate practical performance car (discuss). And while the CSL doesn’t thumb its nose at such matters – it has rear seats and a decent boot, while air-con and a radio were options – it isn’t a car I’d want to drive every day.

The ride is very firm, for starters: more akin to the tightly-damped GT3 than a regular M3. And the lack of sound deadening puts your ears under constant assault, from wind noise, tyre roar and, of course, that freer-breathing straight-six. Around town, it feels like a caged animal, the ageing SMG ’box venting its frustration with occasionally clunky shifts.

All of that is soon forgotten once you find the right road, though. With no turbo to spool up, throttle response is instant, the engine exploding to 8,000rpm as the gearbox bangs through the ratios with brutal ferocity.

For all its straight-line performance, it’s the CSL’s handling that elevates it to legend status, though. The last car I drove that felt so tied-down yet throttle-adjustable was a Porsche Cayman GT4. High praise indeed for a BMW 3 Series first launched in 2003.

The steering is utterly sublime, too, while the chunky Alcantara-wrapped wheel and snug glassfibre buckets add to the road-legal-racer feel.

Reliability and running costsBMW M3 CSL review: Retro Road Test

Official fuel economy for the E46 CSL is just 23.7mpg, although you’ll be lucky to see mid-teens if you drive one hard. Likewise, CO2 emissions of 287g/km mean annual car tax (VED) of £309.75. Consumables, such as tyres, clutches and brake pads, are expensive too.

On the plus side, the engine – including its Vanos variable valve timing – is reliable if properly serviced. And there are plenty of specialists that cater for M cars, usually with lower labour rates than BMW dealerships.

Could I drive it every day?BMW M3 CSL review: Retro Road Test

A CSL is a bit like a Jägerbomb: stimulating and intoxicating, but you wouldn’t want one for breakfast. As I mentioned previously, it’s a bit too single-minded for commuting or ferrying the kids to school. This is a special car best saved for special occasions.

The ideal place to experience a CSL, of course, is on-track. But I suspect very few still see action on circuits: more likely they are tucked up in air-conditioned garages. Such is the fate of the appreciating classic car.

How much should I pay?BMW M3 CSL review: Retro Road Test

Appreciating? You bet. Paul Michaels, Chairman of Hexagon Classics, tells me CSL values shot up 20% in eight months, although they have stabilised now. “You’ll pay £40k – £50k for a car with high miles,” he explains, “but the best examples are nudging £100k”.

A total of 1,400 M3 CSLs were built, including 422 right-hand-drive cars for the UK. Only two colours were offered: Black Sapphire Metallic and Silver Grey Metallic, but black is rarer and thus worth slightly more.

This particular CSL has covered 37,500 miles is for sale at £69,995. Hexagon also has a Silver Grey example with just 20,200 miles for £79,995. Not bad for a car that cost £58k when new.

What should I look out for?BMW M3 CSL review: Retro Road Test

Let’s defer once again to Paul Michaels, who sold BMWs for 46 years. “Service history is absolutely vital,” he says. “Values have increased, but it still isn’t economical to spend large sums restoring them. You could throw a lot of money at a bad CSL.”

Check the service indicator lights on the dashboard aren’t illuminated and scour the paperwork. The car should have had its first oil-change at 1,000 miles, followed by intermediate (Inspection 1) and major (Inspection 2) services at annual intervals. The Inspection 2 includes a valve clearance check: missing it could result in Vanos problems.

One well-known M3 issue, not unique to the CSL, is a cracked boot floor – caused by wear in the subframe mounts. If caught early, it’s a minor repair, but once the floor is damaged, the only option is to weld in a new one: a minimum of £1,500.

Parts are still available, but CSL-specific items, such as the carbon front bumper, can be frighteningly expensive. Remember, originality is key to future value, so check bodywork and interior trim carefully. And steer clear of cars with aftermarket modifications.

Should I buy one?BMW M3 CSL review: Retro Road Test

On paper, the CSL doesn’t stack up. You could have 90% as much fun in an E46 M3 for 20% of the price.

However, the most iconic M Power BMWs are following the lead of Porsches and rocketing in value. And that makes the CSL – arguably the greatest M3 of all – a potentially savvy investment.

Still, let’s forgot money and talk about the car. It’s only February, but I doubt I’ll drive anything more exciting this year. When the oil has run dry and we’re all moving from A to B in autonomous electric pods, the CSL will be looked back upon wistfully as a legendary driver’s car. It hard-wires itself into your head like a craniotomy, leaving your mouth dry, your palms damp and your soul stirred.

If that sounds like hyperbole, I apologise. Perhaps I’ve been swept up in the CSL’s almighty sound and fury. Ultimately, if I had £70k to spend, the lack of a manual gearbox would steer me towards a Porsche 996 GT3. But the CSL has earned its place in my dream garage.

Pub factBMW M3 CSL review: Retro Road Test

The 2005-2006 M3 CS cherry-picks some of CSL’s best bits for a fraction of the price. These include the steering rack, brakes and springs, plus a slightly wider version of those gorgeous alloys. Pay £20k for a good one.

Paul Michaels also tips the BMW Z4 M Coupe as one to watch: “Just look at what’s happened to values of the Z3 M Coupe,” he says. “Classic BMWs don’t get the recognition they deserve at the moment, but I think that will change.”