While it is nice to test tuned and personalised M3s and M4s with north of 500hp, and M5s with over 700hp, the majority of BMW enthusiasts do not have the resources to buy such a car and then embark on an expensive tuning programme.
The good news is that even mainstream BMWs are born with the family DNA and are potentially interesting drivers’ cars as well. It is just a matter of tapping into their inherently sporting genes and then adding some extra spice to create an engaging daily driver that will not break the bank.
The key to doing this effectively is the knowledge to gauge just how much the engine and chassis can be uprated within a given budget, and without compromising the intrinsic balance of the base car. Achieving this fine balance requires more than just pure engineering skill; it also requires input from experienced and sensitive drivers. Luckily, this is a combination that Miami-based Active Autowerke has turned into an art form over the years.
Situated on an industrial estate west of Miami Airport, Active Autowerke was founded in 1985 by brothers, Mike and Karl Hugh. Their workshop and showroom was remodelled out of the car repair and body shop business started by their father. Since then, hard work and experience as well as imagination and huge enthusiasm have turned their BMW tuning business into an internationally known brand.
Over the years I have driven several of the big horsepower M3 and M4 conversions Active Autowerke have created for their customers. While these cars showcase their ability to realise the dreams of their wealthier clients, their expertise shines equally brightly for normal customers at the other end of the BMW model spectrum.
Embodying some of Active’s more modest tuning offerings, the white M2 and the 340i I have come to drive today look personalised yet remain relatively understated. Importantly, both punch well beyond their weight.
As good as the stock M2 Coupe is, particularly in the chassis department, it took less than a mile behind the wheel of the Active Autowerke car to confirm that just a handful of carefully chosen key components are needed to eke out the full potential lurking just below the surface of BMW’s mini-bombshell.
The mechanical changes made to this car are surprisingly modest, but they make a big difference to its raw performance. Even at a canter, the feeling of riding a thoroughbred racehorse quickly comes to mind.
The Active demo car is based on a 2016 model year six-speed manual M2 Coupe, for which BMW claims 370hp at 6,500rpm with the rev limit set at 7,000rpm. Peak torque of 465Nm is on tap between 1,400 and 5,560rpm, while over-boost delivers 500Nm for short periods.
The M2’s turbocharged straight-six motor is basically an N55 engine family derivative with components from the S55 motor that powers the M3/M4. New components include larger main bearing shells and the pistons, whose top rings are optimised for the use of grey-cast iron cylinder liners. The crankshaft is the robust M235i unit.
High performance spark plugs and greater heat rating ensure that thermal resistance measures up to the increased output. On that score, the engine has a substantial cooling matrix up front consisting of a massive water radiator, water-cooled charge-air intercooler, and engine and DCT transmission oil coolers.
As with the M3/M4, significant attention was paid to the oil supply to ensure perfect life giving lubrication under racetrack conditions. This gives the tuners more headroom compared to the M235i motor, and the Active Autowerke conversion taps into this.
“At the start of our benchmarking work on the stock engine we saw 333hp at the rear wheels on our Mustang dyno,” Mike explained. “We think the turbocharger is the M235i unit, and so is right on its flow limit at this level. By the time we reached 490 crank horsepower (390hp at the rear wheels) during the development of our Stage 1 conversion, it was clear that it had run out of puff.”
When I drove the car Active had set up the development motor with their prototype upgraded turbocharger kit, which features a machined housing for a larger turbine wheel, and a less restrictive exhaust manifold. This allows the motor to produce 507hp with room to spare.
With the ability to burn all the fuel required to make this level of power, it is important to get as much cool charge air into the engine and at the other side get the spent gases out as fast as possible.
Helping to facilitate this is Active Autowerke’s Aluminium Charge Pipe Kit, which sends a greater volume of air from the turbocharger to their high efficiency Stepped Core Intercooler, and on to the engine. Aiding both mixture cooling and combustion is the Active Autowerke Methanol Injection Kit, whose reservoir is housed on the left side of the boot. This works like the system on the factory M4 GTS and kicks in on full throttle.
The final piece of the engine upgrade puzzle is the Active Autowerke Performance Software ECU Re-flash that tailors the fuelling, ignition and boost curves to make the most of the uprated hardware.
Reducing exhaust backpressure on a turbocharged engine helps the engine breath better, thus producing more power. Importantly it also lowers the exhaust gas temperature and the temperature of the exhaust valves. This in turn reduces the thermal load on the engine and its cooling system, which is good for longevity.
By the same token if the engine is running well within its safe thermal range, this also allows you to run more boost, to the benefit of power and torque. To this end the Active Autowerke Signature Exhaust System helps to reduce backpressure and also adds a more bass rich exhaust note.
A glance at the Active M2 shows that the ride height has been dropped significantly with the fully adjustable BC Racing BR-Type coil-over suspension kit, which is used in conjunction with adjustable camber plates and Swift Springs. As driven on the day the car sat a good 30mm lower than stock so you have to be careful with ramps and speed bumps.
It is not just the slammed ride height that gives this M2 its track ready look. A set of 10.0J x 18-inch BC Racing forged monoblock alloys shod with 275/35ZR18 Michelin Pilot Super Sport tyres squeezes the daylight from the bulged wheel arches. Only the lack of extreme negative camber and a set of race numbers stop this car from looking at home on the starting grid.
I drove the M2 Competition some two months before the Active M2 Coupe. With the M4 motor, carbon-fibre front engine compartment brace, and other tweaks the premium priced 410hp factory car represents another ball game altogether.
Showing 507hp at the flywheel and 405hp at the wheels on the dyno, the Active M2 Coupe not only leaps over the M2 Competition in performance, it also adds its own unique personality. A USP for the enthusiast looking for a more individual expression, this individuality is a valuable bonus since the Competition comes at a huge premium over the M2 Coupe.
With around 90hp more than the M2 Competition the Active car shows the latent potential in the basic M2 recipe. However, in normal driving around town the extra power is not immediately obvious since today’s sophisticated electronic engine management keeps the tweaked engine as docile and flexible as the stock motor.
While the dyno sheets show that the torque on tap trails the factory curve under 3,000rpm, after that the Active car delivers a 20Nm gain till its torque curve peaks at 3,800rpm, then it stays flat all the way to around 5,500rpm. Meanwhile the standard car’s less beefy torque curve has peaked at 3,600rpm and started to head downhill. In practice, because the motor picks up revs so quickly this slight sub-3,000rpm weakness is hardly noteworthy on the road unless you insist on driving at low crankshaft speeds in a high gear.
On the open road where you can nail the throttle and explore the full rev band. the change in character of the Active engine is dramatic. The sharper response, the greater thrust in the mid-range, and the unrelenting charge towards the red paint in each gear makes it feel like a different car. The fact that it will also leave an M2 Competition in the dust is an added bonus. This is a supercar killer on a budget!
The uprated suspension and big wheels are a matter of taste, and do make the ride more edgy on bumpy roads. That said track junkies will appreciate the relative lack of roll and larger tyre contact patches that nicely contain the extra power.
The one addition I would make if the car were mine would be a big brake kit. The BMW M set up is fine for the road, but with this level of power more effective stoppers would be a good idea on track.
If you already have an M2 in your garage, or plan to buy a pre-owned car and use the difference to add more smiles per mile, the comparatively moderate investment for the Active Autowerke Stage 1 conversion rates serious consideration.
If you need a compact four-door saloon that is fun to drive the rear-wheel-drive 3-Series saloon has always been the keen drivers’ first choice. And if you live in an area where it rains a lot or snows the xDrive option provides the answer to that question.
Snow is certainly not a problem faced by residents of Miami, and this 2016 model year 340i with the M Sport Package, which is the daily driver of Mike Hugh’s wife Sandra, became potentially interesting once infused with more power and the grip to match.
Sandra is no fan of stiff riding cars so it is no surprise to find that her 340i has been set up to perfectly walk the fine line between a sleeper in town and a champ on a twisty road.
BMW claim 355hp and 500Nm of torque for the 3.0 litre TwinPower Turbo straight six, and Active’s Mustang dyno showed 317hp at the rear wheels. This implies that the motor was actually churning out close to 400hp at the flywheel, which is only 20hp short of the naturally aspirated 5.0 litre V8 in the larger and heavier E39 M5!
The motor came in for attention first and Active Autowerke plugged in their Active-8 piggyback ECU and fitted their Signature stainless steel sports silencer that reduces backpressure and expels spent gases via one polished tailpipe per side.
The subsequent dyno run recorded 380hp at the rear wheels, a gain that equates to a solid 450hp at the flywheel seamlessly deployed to the rear wheels through the smooth and rapid close ratio ZF eight-speed automatic transmission.
As the car has the factory active dampers, it was decided that in the interest of comfort the journey towards improved grip and handling would stop at a set of DOSS 8.5J and 9.5J x 19-inch Flow forged alloy wheels wrapped in 225/40ZR19 and 255/35ZR19 Michelin Pilot Supersport Tyres.
This proved to be an astute move, and the result of these minimal mods is a 340i that looks distinctive without being over the top, and goes much harder than stock but with little or no compromise made to its everyday usability.
In the world of sub-M models, this Active Autowerke conversion for the 340i delivers plenty of bang for your buck, and shows that you don’t need to have or spend a fortune to enjoy ownership of an interesting and engaging BMW.