There are no sacred cows when it comes to the BMW M3. Its first engine was a lightweight four-cylinder, then BMW bumped it up to a straight-6 and later to a small-displacement V8. It wasn't about adhering to some kind of long-forgotten company mandate, it was simply about which engine made the M3 better.
That kind of thinking could make the upcoming 2014 BMW M3 yet another ground-breaking new vehicle when it arrives in about two years. Although initial rumors pointed to the possibility of an inline-6 boosted by a trio of turbochargers, there's another, even more radical change in the works — a V6.
Because a V6 Fits
Yes, a highly advanced 3.0-liter twin-turbo V6 is being developed, according to a BMW insider. The rejection of an inline-6, it's claimed, is for reasons of packaging. The new V6 will be the first to mount its two twin-scroll turbochargers within the vee-angle, mirroring the company's 4.4-liter V8 design. This unique-to-BMW approach reduces the length of the inlet tract compared with a regular turbo-vee setup, helping to sharpen throttle response and minimizing heat buildup after air passes through the intercooler.
The V6 apparently won't be simply a cut-down version of the BMW V8, even though history records the M3's 4.0-liter V8 as a chopped version of the old M5 V10, with an identical bore and stroke. A two-cylinder cut of the 4,395cc V8 results in a 3,270cc capacity, yet our insider insists that a 3.0-liter capacity is most likely.
In theory, a 60-degree vee offers the best primary balance for a six; however, a 90-degree angle is required for the two turbos to fit. BMW must then solve the imbalance issue by using either balance shafts or a unique firing order, as it did with the 90-degree V10 in the E60 M5. Outputs of the unique-to-M3 engine are believed to be around 429 horsepower and 405 pound-feet of torque: sufficient to fend off the Audi RS4 and Mercedes C63 AMG. Improved direct injection, extra boost and a higher compression ratio will all contribute to the advantage the V6 will have over the BMW 1M's 3.0-liter twin-turbo straight-6.
So while the new twin-turbo V6 does seem the likely power source for the new M3, it also signals the end of a high-revving naturally aspirated engine for the car, a format synonymous with the badge over the past 26 years.
Shaving Pounds Where They Count
The next M3 will also be larger, yet lighter than the outgoing generation. Although the new F30 3 Series sedan is 3.7 inches longer than the E90, on average the range weighs 88 pounds less, thanks to alloy chassis components and increased use of ultra-high-tensile steel throughout the body. Further weight-loss strategies will be employed in the M3, with the M3 CRT concept previewing the advances.
Lightweight design components include a carbon honeycomb hood weighing around 6.6 pounds, titanium mufflers and carbon composite panels and seat parts. Aluminum wiring for the car's electronics replaces heavier copper, saving another 15-20 pounds overall.
BMW is reportedly working on carbon-ceramic discs and aluminum calipers — saving 33 pounds on each corner — but this expensive tech will likely be introduced late in the car's life cycle. Expect the M3 to tip the scales close to 3,483 pounds, which would be about 75 pounds less than the current coupe. Electric power steering — not fitted to the new M5 — is a possibility for the new M3, while a six-speed manual will continue alongside a revised seven-speed dual-clutch gearbox.
The E92's electronics — including adaptive dampers and M-Sport differential — will be revised to complement the new 3 Series' wider tracks.
The Internal Word
For the first time, the M3 will get a unique code name, tipped to be F80 for the sedan and F82 for the coupe and convertible. Also for the first time, the M3 four-door sedan will launch before the two-door body styles. Debate continues inside Munich over the possibility of renaming the 3 Series coupe and convertible as the 4 Series; however, a name change to M4 is something the M division is apparently actively against.
When the M3/M4 debuts in early 2014, it will need to comply with Euro 6 emissions standards and substantially undercut both the E92's 11.9L/100km and 1M's 9.6L/100km consumption ratings, while achieving a low-4-second 0-60-mph time. That's the new-age performance-car balancing act facing the M division engineers — more power and reduced emissions, all while maintaining crisp throttle response and high rev-ability. It's not easy, but when you are free to use any means possible, it sure makes things easier.
Portions of this content have appeared in foreign print media and are reproduced with permission.