Z4 vs 911
BMW brings the Z4; Porsche answers with the 911. Both play in the sports car class. On balance, the 911 is the stronger package: it leads in 3 out of 4 areas, most clearly in engine & performance.
At a glance
- Engine & Performance 911 wins
- Fuel Economy & Range Z4 wins
- Space & Practicality 911 wins
- Off-road & Towing 911 wins
- Engine & Performance2.1
- Fuel Economy & Range6.0
- Engine & Performance4.1
- Fuel Economy & Range2.0
Spec scores (0 to 10) are calculated from manufacturer specs against other models in the same class. See how the formula works. They are not reviews or user ratings.
Key Differences
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The 911 has 133 hp more power
A clear win for the 911: 388 hp against 255 hp. Few specs in this matchup are as one-sided. The 911’s extra output gives it more in reserve when you need to get up to speed.
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The 911 has room for 4 seats
Here the 911 pulls well ahead of the Z4, with 4 seats compared to 2 seats. Extra seats mean you can take more people along without taking a second car.
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The Z4 has better fuel economy
The Z4 doesn’t just edge this one; 28 mpg against 21 mpg is a lead you’ll feel. The Z4 uses less fuel on the standard combined cycle, which matters most if you drive a lot.
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The Z4 has better city fuel economy
Big gap, real consequences. The Z4’s 25 mpg versus the 911’s 18 mpg changes how the two compare in daily use. In town, driving style has a big effect, but the Z4 starts from a better baseline.
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The Z4 has better highway fuel economy
The 911 is clearly behind on fuel economy (highway) (25 mpg against 33 mpg), and that’s one of its biggest weak spots in this matchup. Highway fuel economy matters if you cover long distances at steady speeds.
Design & Size
Engine & Performance
911 leads
The engine & performance numbers point firmly in one direction: toward the 911. The 911 delivers 133 hp more power. More power helps with merging, overtaking and climbing hills, especially with passengers and luggage on board. Net result: the 911 leads this part of the comparison.
Total system output
Z4: 255 hp 911: 388 hp Power is only part of the story; weight, gearing and torque delivery shape how quick a car feels.
Torque
Z4: 295 lb-ft 911: 331 lb-ft Electrified powertrains deliver torque instantly, so compare torque figures alongside the powertrain type.
Fuel Economy & Range
Z4 leads
This section belongs to the Z4. In fuel economy & range, it leads the 911 by a margin that’s hard to ignore. Point to the Z4 for better fuel economy. Official figures rarely match real-world driving exactly, but the ranking between two cars tends to hold. Weighing only fuel economy & range, the Z4 comes out ahead.
Fuel economy (combined)
Z4: 28 mpg 911: 21 mpg Better combined fuel economy lowers your running costs every week, and the savings add up over years of ownership.
Fuel economy (city)
Z4: 25 mpg 911: 18 mpg City fuel economy matters most if your driving is mostly short trips, traffic and stop-and-go commutes.
Space & Practicality
911 leads
In this area the 911 has a lead the Z4 can’t close. The 911 answers with room for 4 seats. The 911 has room for more passengers, useful for growing families and carpools. For space & practicality, the 911 is the one to beat.
Seats
Z4: 2 seats 911: 4 seats Third-row seats are often best for kids, so check legroom figures if adults will sit there.
Off-road & Towing
911 leads
This area is close, with the 911 just ahead of the Z4. The 911 pulls ahead with available all-wheel drive. The 911 offers all-wheel drive; the Z4 doesn’t, which matters if you face harsh winters. The off-road & towing verdict goes to the 911.
AWD / 4WD available
Z4: no 911: yes All-wheel drive helps you get going on slippery roads, but good tires matter just as much for stopping and turning.
Safety & Tech
The safety & tech entries below are descriptive rather than numeric. Read them side by side to see where the Z4 and the 911 part ways.
Full Specifications
Engine & Performance
| Spec | Z4 | 911 |
|---|---|---|
| Powertrain | Gas | Gas |
| Engine | 2.0L turbo I4 | 3.0L twin-turbo flat-6 |
| Total system output | 255 hp | 388 hp (winner) |
| Torque | 295 lb-ft | 331 lb-ft (winner) |
| Transmission | 8-speed automatic | 8-speed dual-clutch (PDK) |
| Drivetrain | RWD | RWD (AWD available on Carrera 4 models) |
Fuel Economy & Range
| Spec | Z4 | 911 |
|---|---|---|
| Fuel economy (combined)EPA estimate where available | 28 mpg (winner) | 21 mpg |
| Fuel economy (city) | 25 mpg (winner) | 18 mpg |
| Fuel economy (highway) | 33 mpg (winner) | 25 mpg |
Space & Practicality
| Spec | Z4 | 911 |
|---|---|---|
| Seats | 2 seats | 4 seats (winner) |
Off-road & Towing
| Spec | Z4 | 911 |
|---|---|---|
| AWD / 4WD available | No | Yes (winner) |
Safety & Tech
| Spec | Z4 | 911 |
|---|---|---|
| Basic warranty | 4 yr / 50,000 mi | 4 yr / 50,000 mi |
“N/A” means the manufacturer does not specify the value or we could not confirm it. Figures marked “manufacturer rating” are the maker’s own claims, not our measurements.
Which One Should You Buy?
Choose the Z4 if…
- you want better combined fuel economy (28 mpg vs 21 mpg)
- you want better city fuel economy (25 mpg vs 18 mpg)
- you cover long highway distances (33 mpg vs 25 mpg on the highway)
Choose the 911 if…
- you merge, overtake or climb hills with a full load (388 hp vs 255 hp)
- you regularly carry extra passengers (4 seats vs 2 seats)
- you want more pulling power from low speeds (331 lb-ft vs 295 lb-ft of torque)
- you face snow, ice or slippery back roads
Also Compared
Frequently Asked Questions
Which is better for most people, the Z4 or the 911?
The 911 wins more of the areas we compared, so it’s the safer pick unless you know that better fuel economy would make a real difference in your routine.
Executive Summary
Let me cut through the brand noise around the Z4 and the 911. What tips it for me is that the 911 has 133 hp more power. And if that weren’t enough, the 911 has room for 4 seats. The Z4 does have a strong card to play: better fuel economy.
The Z4 makes sense for anyone who values fuel economy & range; the 911 for anyone who values engine & performance.
My pick: if it were my money, the 911, unless what you want most is better fuel economy.
Personal opinion based on the data above. Your priorities may differ.