BMW is among the world’s most recognizable auto brands, known far and wide for their various numbered series of sedan cars. Each generation has brought something new to the range, be it technological or design innovation.
Here we focus on a key stage in the evolution of the BMW 3 Series, which first rolled off the production lines back in May 1975. The BMW E46 was also known as the fourth-generation 3 Series. In particular, we explore in more depth the E46 M3 which has become an enthusiast craze and has seen the older models climb back up in price.
BMW E46 Background:
The E46 first went into production in December 1997, running until the summer of 2006. It came in 5 main body styles: 4-door sedan, 2-door coupe, 2-door convertible, 5-door wagon (Touring) and a 3-door hatchback. There was, of course, also an ‘M’ version of the E46, which was made from 2000 to the end of the overall series run in 2006.
Read more about the E46 vs the E39 in our head to head comparison
The standard E46 gasoline engine ranged from 1.6 to 2.0L, and also included diesel options from 2.0 to 3.0L, all depending on the exact specification you bought.
The E46 was a notable 3 Series because it was the model that marked the reintroduction of AWD drivetrains into the 3 Series. It was also the first to use BMW’s “Valvetronic” technology, which is the system of variable valve lift, as well as satellite navigation, rain-sensing windshield wipers, LED taillights and more.
It was eventually phased out of production starting in 2004 as the company started to introduce the E90.
BMW E46 M3
The then much-anticipated E46 M3 was introduced in later 2000. It was sold as a 2-door coupe or a 2-door convertible, as is still common practice with the latest M models of the 3 and 4 Series cars. Let’s start by looking at the basic specifications of this M3.
E46 M3 Specs
Here’s a summary of the main E46 M3 specs for production starting in October 2000. A total of just under 86,000 units were produced in total --- 56,000 coupes and 30,000 convertibles, approximately --- and all were powered by the 3.2L S54 engine as standard.
- 0-60 Time: 5.1 seconds
- Top speed (OEM): 155mph
- Engine: S54 straight-six 3.2L
- Transmission: Getrag 420G 6-speed manual; SMG-II 6-speed automatic
- Wheelbase: 107”
- Length: 177”
- Width: 70”
- Height: 54”
E46 M3 Engine
The new M3 made use of the then-new S54 engine, which went into production at the same time as the M3 itself. It was the high-performance equivalent of the M54 that was used in the standard BMW 3 Series sedan models, and an evolution of the S50 from the previous generation.
The E46 M3 engine held a number of advantages over its predecessor, the S50. It did carry the same style of cast-iron engine block, but it had a significantly higher standard redline of 8,000rpm. The S50 top redline was the S50B32, which redlined at 7,600rpm and was used in the 1995 E36 M3 model.
Below were some of the changes made to the E46 M3 engine (S54)
- New camshafts that featured BMW’s VANOS technology (variable valve timing)
- Compression ratio raised to 11.5:1 (previously was 11.3:1)
- ECU replaced with a Siemens MSS 54
- Electronic throttle control introduced
- Bore raised to 87mm, giving a bigger 3.2L displacement.
In fact, the S54 was the last in its direct line of naturally aspirated straight-six engines. In subsequent M3 models, a totally new series of V8 engines was adopted (S65), which were not part of the same engine family.
Special Edition: BMW E46 M3 CSL
True to its tradition of special-edition and limited-production models, BMW created the E46 M3 CSL, which stood for Coupe Sport Leichtbau. For those who don’t speak German, “Leichtbau” means Lightweight. It arrived in 2004 with production extremely limited to just under 1,400 units. Modern fans of the brighter and more garish yellow M3 and M4 models would not have been happy at the time to see that this special-edition E46 M3 CSL was only available in two colors: Silver Grey Metallic and Black Sapphire Metallic.
At the heart of the CSL edition, of course, was the upgraded E46 M3 engine. This version of the S54 was booted by 17hp and 4lb-ft of torque in total. BMW achieved this boost by using camshafts with a sharper profile, a larger air intake that also featured a carbon fiber manifold, and swapped-out exhaust valves. This engine was only paired with the SMG-II automatic transmission. No manual transmission was offered.
The CSL was all about providing a model with a lighter curb weight than the regular E46 M3, which weighed in at 3,416 pounds, or 1,570kg. The Leichtbau delivered on its namesake promise, shedding some 243lbs from the main model, aching 3,053lbs as the final curb weight. How was this managed?
- Glass-reinforced plastics used within the car’s structure
- Carbon fiber-reinforced plastic roof and carbon fiber body panels
- Lower center of gravity
- Thinner glass in the rear window
- Getting rid of sound insulation, navigation, a/c and stereo
- And more…
There was some scandal created by a report on the world-renowned (and sometimes totally infamous) British auto show Top Gear, when they claimed that the trunk floor cover was made of cardboard! It was, in fact, fiberboard. Regardless of how badly you want your “Leichtbau” to live up to its name, there are some steps that would be too far for any reputable auto brand.
Carbon fiber was used in other places, too, including as the front splitter and rear diffuser, both of which boost aerodynamism and downforce on the E46 M3 CSL. It also had a raised lip on the trunk, as opposed to flat design on the regular E36 M3 specs.
Other improvements to the E46 M3 CSL included larger 19-inch alloys, semi-slick tires and a new suspension system with better shock absorbers and stiffer springs. Within this list, the tires probably stood out the most, and attested to the fact that the E46 M3 CSL was best-suited to the track, in reality.
The semi-slick tires were actually superior in grip to regular street tires, but only after being warmed up as they would be on the track. When they were used on slick roads after a rain shower, they proved less up to the task.
Conclusion: A Great Leap Forward
The E46 M3 was a fitting evolution to take the BMW 3 Series forward into a new millennium. There were many technological and mechanical firsts, as well as a raft of special editions to mark other milestones in the car’s development. The E46 model continues to be popular among collectors and BMW driving fans alike. Even now, an E46 M3 model might go for more than $50,000.
As these continue to age and eventually enter the realm of BMW classics, it’s always interesting to look back and reflect on how far the newest 3 Series and M3 models have come since then.