Sweet Dream: BMW M4 CSL

We were sitting in the MOTOR kitchen the other day when an argument erupted.

What’s the best M3 ever? Is it the deep-voiced, V8 E90? Is it the nimble, legendary little E30? Or is it the stripped-out E46 CSL?

It’s a hard one and an argument we’ll extend to our Facebookers as well. Until then, the MOTOR staff agreed, after some hair-pulling, the E46 CSL is the ultimate M3.

It bows to the lightweight ethos of the E30, has perhaps the best engine that’s ever sat under an M3’s bonnet (the glorious, 3.2-litre naturally aspirated S54 straight six) and, well, it looked tits.

Not to mention, while the SMG II gearbox made a lot of people cranky back in the day, today it’s winning hearts for being a little more interactive and characterful than the ever-ubiquitous, modern dual-clutch.

Now, there’s nothing wrong with the new M4 but, as we’ve already alluded, it doesn’t quite have enough tabasco sauce for us.

Yes, it has 317kW and, at 1497kg, you wouldn’t call it obese. But imagine cutting 100kg out of it and adding a handful extra herbs (the E46 sported an extra 13kW and 5Nm) and suddenly, you’ve got one deliciously sweet dream on your hands.

BMW itself has its own vision with the forthcoming M4 GTS, but we're not sure it goes far enough.

Engine: Thanks to the original S54 engine being of such high calibre, the E46 CSL managed to only extract a small amount of extra power. Given the F82 M4 has, sadly, ditched natural aspiration, at least twin turbos mean it could be easily wicked-up for some serious power outputs beyond its stock 317kW and 550Nm.

Gearbox: The M4 CSL should come in manual for a better driving experience. The E46 CSL had the SMG II, which was basically a manual gearbox that changed gears itself, but a manual would bring the tech-heavy M4 back to earth. Plus, it weighs less.

Brakes: You can option carbon ceramic brakes on your M4 but for the CSL we reckon pinch the brakes from the F10 M5 – six-pot calipers munching 400mm discs. Carbon ceramic, of course. It worked for the E46 CSL, which used the bigger brakes off the E39 M5.

Interior: The E46 ditched sound deadening, sat-nav and electric seats. It didn’t even have air con or a stereo, though both were no-cost options. The M4 CSL could score a similar treatment and drop 100kg after a Biggest Loser-esque makeover. Weight drops to 1397kg.

Exterior: The E46 CSL had special, carbon-dripping front and rear diffusers which improved downforce over the stock M3 by 50 per cent. It also had this distinctive, Marilyn Monroe mole-esque hole to feed a cold air intake. Bring it back for M4 CSL.

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