Certified Benz & Beemer Compares 2016 BMW Z4 VS 2015 Mazda MX-5 Near Scottsdale, AZ

Responsive image

2016 BMW Z4

Responsive image

2015 Mazda MX-5

Safety Comparison

The BMW Z4 has Daytime Running Lights to help keep it more visible under all conditions. Canadian government studies show that driving with lights during the day reduces accidents by 11% by making vehicles more conspicuous. The MX-5 Miata doesn’t offer Daytime Running Lights.

The Z4 offers optional Park Distance Control to help warn drivers about vehicles, pedestrians or other obstacles behind or in front of their vehicle. The MX-5 Miata doesn’t offer any parking assist system.

Compared to metal, the Z4’s plastic fuel tank can withstand harder, more intrusive impacts without leaking; this decreases the possibility of fire. The Mazda MX-5 Miata has a metal gas tank.

The Z4 has standard BMW Assist, which uses a global positioning satellite (GPS) receiver and a cellular system to remotely unlock your doors if you lock your keys in, help track down your vehicle if it’s stolen or send emergency personnel to the scene if any airbags deploy. The MX-5 Miata doesn’t offer a GPS response system, so if you’re involved in an accident and you’re incapacitated help may not come as quickly.

Both the Z4 and the MX-5 Miata have standard driver and passenger frontal airbags, front side-impact airbags, side-impact head airbags, front seatbelt pretensioners, four-wheel antilock brakes, traction control and electronic stability systems to prevent skidding.

The BMW Z4 weighs 644 to 1069 pounds more than the Mazda MX-5 Miata. The NHTSA advises that heavier cars are much safer in collisions than their significantly lighter counterparts. Lighter cars are also affected more by crosswinds.

Warranty Comparison

The Z4 comes with a full 4 year/50,000 mile basic warranty, which covers the entire car and includes 24 hour roadside assistance. The MX-5 Miata’s 3 year/36,000 mile basic warranty expires 1 year and 14,000 miles sooner.

The Z4’s corrosion warranty is 7 years longer than the MX-5 Miata’s (12 vs. 5 years).

BMW pays for scheduled maintenance on the Z4 for 4 years and 50,000 miles. BMW will pay for oil changes, lubrication and any other required maintenance. Mazda doesn’t pay scheduled maintenance for the MX-5 Miata.

Reliability Comparison

To reliably power the ignition and other systems and to recharge the battery, the Z4 has a standard 170-amp alternator. The MX-5 Miata’s 100-amp alternator isn’t as powerful.

The battery on the Z4 is in the trunk, which protects it from hot underhood temperatures which can degrade battery life. By keeping the Z4’s battery 20 to 30 degrees cooler, its life is increased by years. The MX-5 Miata’s battery is in the hot engine compartment.

J.D. Power and Associates’ 2015 Initial Quality Study of new car owners surveyed provide the statistics that show that BMW vehicles are better in initial quality than Mazda vehicles. J.D. Power ranks BMW 6th in initial quality, above the industry average. With 24 more problems per 100 vehicles, Mazda is ranked 23rd, below the industry average.

Engine Comparison

The Z4 has more powerful engines than the MX-5 Miata:



Z4 sDrive28i 2.0 turbo 4 cyl.

240 HP

260 lbs.-ft.

Z4 sDrive35i 3.0 turbo 6 cyl.

300 HP

300 lbs.-ft.

Z4 sDrive35is 3.0 turbo 6 cyl.

335 HP

332 lbs.-ft.

MX-5 Miata automatic 2.0 DOHC 4 cyl.

158 HP

140 lbs.-ft.

MX-5 Miata manual 2.0 DOHC 4 cyl.

167 HP

140 lbs.-ft.

As tested in Car and Driver the Z4 sDrive28i 2.0 turbo 4 cyl. is faster than the MX-5 Miata manual (manual transmissions tested):


MX-5 Miata

Zero to 60 MPH

5.6 sec

7 sec

Zero to 100 MPH

15.7 sec

20.2 sec

Quarter Mile

14.4 sec

15.4 sec

Speed in 1/4 Mile

96 MPH

90 MPH

Top Speed

155 MPH

134 MPH

As tested in Car and Driver the Z4 sDrive35i 3.0 turbo 6 cyl. is faster than the MX-5 Miata automatic (automatics tested):


MX-5 Miata

Zero to 60 MPH

4.8 sec

7 sec

Zero to 100 MPH

12 sec

21.1 sec

Quarter Mile

13.5 sec

15.6 sec

Speed in 1/4 Mile

106 MPH

89 MPH

Fuel Economy and Range Comparison

On the EPA test cycle the Z4 gets better fuel mileage than the MX-5 Miata:


MX-5 Miata

4 cyl./Manual

22 city/34 hwy

22 city/28 hwy

4 cyl./Manual


21 city/28 hwy

4 cyl./Auto

22 city/33 hwy

21 city/28 hwy

Regenerative brakes improve the Z4’s fuel efficiency by converting inertia back into energy instead of wasting it. The MX-5 Miata doesn’t offer a regenerative braking system.

In heavy traffic or at stoplights the Z4 sDrive28i Manual’s engine automatically turns off when the vehicle is stopped, saving fuel and reducing pollution. The engine is automatically restarted when the driver gets ready to move again. (Start/Stop isn’t accounted in present EPA fuel mileage tests.) The MX-5 Miata doesn’t offer an automatic engine start/stop system.

The Z4 has 1.8 gallons more fuel capacity than the MX-5 Miata (14.5 vs. 12.7 gallons), for longer range between fill-ups.

Brakes and Stopping Comparison

For better stopping power the Z4’s brake rotors are larger than those on the MX-5 Miata:

Z4 sDrive28i

Z4 sDrive35i

MX-5 Miata

Front Rotors

13 inches

13.7 inches

11.4 inches

Rear Rotors

11.8 inches

12.8 inches

11 inches

The Z4’s standard front and rear disc brakes are vented to help dissipate heat for shorter stops with less fading. The rear discs on the MX-5 Miata are solid, not vented.

The Z4 stops much shorter than the MX-5 Miata:


MX-5 Miata

80 to 0 MPH

206 feet

237 feet

Road & Track

70 to 0 MPH

161 feet

174 feet

Car and Driver

60 to 0 MPH

102 feet

120 feet

Motor Trend

60 to 0 MPH (Wet)

130 feet

138 feet

Consumer Reports

Tires and Wheels Comparison

For better traction, the Z4 has larger standard tires than the MX-5 Miata (225/45R17 vs. 205/50R16). The Z4’s optional tires are larger than the largest tires available on the MX-5 Miata (F:225/40R18 & R:255/35R18 vs. 205/50R16).

The Z4 sDrive28i’s standard tires provide better handling because they have a lower 45 series profile (height to width ratio) that provides a stiffer sidewall than the MX-5 Miata’s standard 50 series tires. The Z4’s optional 225/35R19 front and 255/30R19 rear tires have a lower 35 series front and 30 series rear profile than the MX-5 Miata Club/Grand Touring’s 45 series tires.

For better ride, handling and brake cooling the Z4 sDrive28i has standard 17-inch wheels. Smaller 16-inch wheels are standard on the MX-5 Miata. The Z4’s optional 19-inch wheels are larger than the 17-inch wheels on the MX-5 Miata Club/Grand Touring.

Changing a flat tire near traffic can be dangerous and inconvenient. The run-flat tires standard on the Z4 can be driven up to 50 miles without any air pressure, allowing you to drive to a service station for a repair. The MX-5 Miata doesn’t offer run-flat tires.

Suspension and Handling Comparison

The Z4 offers an optional driver-adjustable suspension system. It allows the driver to choose between an extra-supple ride, reducing fatigue on long trips, or a sport setting, which allows maximum control for tricky roads. The MX-5 Miata’s suspension doesn’t offer adjustable shock absorbers.

For a smoother ride and more stable handling, the Z4’s wheelbase is 6.6 inches longer than on the MX-5 Miata (98.3 inches vs. 91.7 inches).

For better handling and stability, the track (width between the wheels) on the Z4 is .8 inches wider in the front and 2.5 inches wider in the rear than on the MX-5 Miata.

The Z4 sDrive35is handles at .91 G’s, while the MX-5 Miata Grand Touring pulls only .85 G’s of cornering force in a Road & Track skidpad test.

The Z4 sDrive35is goes through Road & Track’s slalom faster than the MX-5 Miata Grand Touring (67.8 vs. 67 MPH).

The Z4 sDrive35i executes Motor Trend’s “Figure Eight” maneuver 1.5 seconds quicker than the MX-5 Miata Club (25.2 seconds @ .74 average G’s vs. 26.7 seconds @ .67 average G’s).

Chassis Comparison

As tested by Road & Track, the interior of the Z4 sDrive35i is quieter than the MX-5 Miata Grand Touring:


MX-5 Miata

At idle

46 dB

55 dB


76 dB

82 dB

50 MPH Cruising

72 dB

74 dB

70 MPH Cruising

74 dB

79 dB

Passenger Space Comparison

The Z4 has 1.7 inches more front headroom and .1 inches more front shoulder room than the MX-5 Miata.

Cargo Capacity Comparison

The Z4 has a much larger trunk with its top down than the MX-5 Miata (6.4 vs. 5.3 cubic feet).

A low lift-over trunk design makes loading and unloading the Z4 easier. The Z4’s trunk lift-over height is 27.2 inches, while the MX-5 Miata’s liftover is 31.6 inches.

Ergonomics Comparison

The engine computer on the Z4 automatically engages the starter until the car starts with one twist of the key and disables the starter while the engine is running. The MX-5 Miata’s starter can be accidentally engaged while the engine is running, making a grinding noise and possibly damaging the starter and ring gear.

To help each driver find a more comfortable driving position, the Z4 has a telescoping steering wheel. Much better than just a tilt steering wheel or adjustable seat, this allows a short driver to sit further from the steering wheel while maintaining contact with the pedals. The MX-5 Miata doesn’t offer a telescoping steering wheel.

When two different drivers share the Z4, the memory system makes it convenient for both. Each setting activates different, customized memories for the driver’s seat position, outside mirror angle and climate settings. The MX-5 Miata doesn’t offer a memory system.

The Z4’s front and rear power windows all open or close fully with one touch of the switches, making it more convenient at drive-up windows and toll booths, or when talking with someone outside the car. The MX-5 Miata’s standard power window switches have to be held the entire time to close them fully. Only its driver’s window opens automatically.

The Z4’s standard power window controls are mounted on the armrest for easy access. The MX-5 Miata’s available power window controls are spread out on the center console where they can’t be seen without the driver completely removing his eyes from the road.

If the windows are left down on the Z4 the driver can raise them all using the key in the outside lock cylinder or the keyless remote; on a hot day the driver can lower the windows. The driver of the MX-5 Miata can only raise the windows from inside the vehicle, with the ignition on.

In case of a sudden change of weather, the Z4 has a standard remote convertible top which can be raised from a distance to protect the interior of the vehicle from damage. The MX-5 Miata doesn’t offer a remote top, so the driver will have to run to the car, get in, turn the ignition on (with available power top) and raise the top to prevent the interior from being damaged.

The Z4’s standard power locks allow the driver or passenger to lock or unlock all the doors at a touch without leaning over. Power locks cost extra on the MX-5 Miata.

The MX-5 Miata’s optional power locks don’t automatically lock the doors. The Z4’s standard doors lock when a certain speed is reached. This is an important feature for occupant safety. Locked doors are proven to open less often in collisions, and they are also effective in preventing crime at traffic lights. (The power lock’s automatic feature may have to be activated by your dealer.)

The Z4’s rain-sensitive wipers adjust their speed and turn on and off automatically based on the amount of rainfall on the windshield. This allows the driver to concentrate on driving without constantly adjusting the wipers. The MX-5 Miata’s manually variable intermittent wipers have to be constantly adjusted.

In poor weather, headlights can lose their effectiveness as grime builds up on their lenses. This can reduce visibility without the driver realizing. The Z4 offers available headlight washers to keep headlight output high. The MX-5 Miata doesn’t offer headlight washers.

The Z4 has a standard automatic headlight on/off feature. When the ignition is on, the headlights automatically turn on at dusk and off after dawn. The MX-5 Miata doesn’t offer automatic headlights.

While driving with high beams on, sensitive light sensors available for the Z4 detect other vehicles which could be blinded and automatically switch to low beams. The MX-5 Miata doesn’t offer automatic dimming high beams.

To help drivers see further while navigating curves, the Z4 has standard adaptive headlights to illuminate around corners automatically by reading vehicle speed and steering wheel angle. The MX-5 Miata doesn’t offer cornering lights.

The Z4’s standard outside mirrors include heating elements to clear off the mirrors for better visibility. The MX-5 Miata doesn’t offer heated side mirrors.

When the Z4 is put in reverse, the passenger rearview mirror tilts from its original position. This gives the driver a better view of the curb during parallel parking maneuvers. Shifting out of reverse puts the mirror into its original position. The MX-5 Miata’s mirror doesn’t automatically adjust for backing.

The Z4 has standard automatic dimming rear and side view mirrors which automatically darken quickly when headlights shine on them, keeping following vehicles from blinding or distracting the driver. The MX-5 Miata offers an automatic rear view mirror, but its side mirrors don’t dim.

On extremely cold Winter days, the Z4’s optional heated steering wheel provides comfort, allowing the driver to steer safely and comfortably before the car heater warms up. The MX-5 Miata doesn’t offer a heated steering wheel.

The Z4’s standard dual zone air conditioning allows the driver and front passenger to choose two completely different temperatures so people with different temperature preferences won’t have to compromise. This makes both the driver and front passenger as comfortable as possible. The MX-5 Miata doesn’t offer dual zone air conditioning.

A built-in pollen filter removes pollen, exhaust fumes and other pollutants from the Z4’s passenger compartment. This helps prevent lung and/or sinus irritation, which can trigger allergies or asthma. The MX-5 Miata doesn’t offer a filtration system.

Optional BMW Apps for the Z4 xDrive35i/xDrive35is allows the driver and passengers access to select programs on their smartphones, including reading text messages aloud, playing internet radio stations, tagging songs to buy them later, following twitter accounts and other connected activities without taking their eyes off the road or their hands from the wheel. The MX-5 Miata doesn’t offer factory integrated smartphone program access.

To direct the driver from any location to a given street address, a GPS navigation system is available on the Z4 xDrive35i/xDrive35is. The Z4’s navigation system also has a real-time traffic update feature that offers alternative routes to automatically bypass traffic problems. (Service not available in all areas.) The MX-5 Miata doesn’t offer a navigation system.

With optional voice command, the Z4 xDrive35i/xDrive35is offers the driver hands free control of the radio and the navigation computer by simply speaking. The MX-5 Miata doesn’t offer a voice control system.

Bluetooth wireless connectivity is standard on the Z4, connecting the driver and passenger’s cell phones to the vehicle systems. This allows them to use the vehicle’s stereo and hand controls to place calls safely and easily. Bluetooth costs extra on the MX-5 Miata.

Recommendations Comparison

Intellichoice recognized the BMW Z4 as a “Best Value of the Year” for the 2015 model year. The Mazda MX-5 Miata didn't win any recognition from Intellichoice.

The Z4 was chosen as one of Automobile Magazine’s “All Stars” in 2010. The MX-5 Miata hasn’t been picked since 2002.

© 1991-2016 Advanta-STAR Automotive Research. All rights reserved. Who We Are
Click here to view the disclaimers, limitations and notices about EPA fuel mileage, crash tests, coprights, trademarks, and other issues.