8 Series vs 718 Cayman
Rivals in the sports car class rarely match spec for spec, and the 8 Series and the 718 Cayman are no exception. Scoring each area separately, the 8 Series comes out on top 4 times out of 4. Its lead is sharpest in engine & performance.
At a glance
- Engine & Performance 8 Series wins
- Fuel Economy & Range 8 Series wins
- Space & Practicality 8 Series wins
- Off-road & Towing 8 Series wins
- Engine & Performance3.7
- Fuel Economy & Range4.1
- Engine & Performance2.5
- Fuel Economy & Range2.7
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 8 Series has room for 4 seats
On seats, the 8 Series posts 4 seats against 2 seats for the 718 Cayman, a gap big enough to feel in everyday use. The 8 Series has room for more passengers, useful for growing families and carpools.
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The 8 Series has 88 lb-ft more torque
This is one of the widest gaps in the whole comparison: 368 lb-ft for the 8 Series versus 280 lb-ft for the 718 Cayman. More torque means stronger pulling from low speeds, which you feel when accelerating from a stop or climbing grades.
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The 8 Series has 35 hp more power
The 8 Series gets a small bonus on total system output, with 335 hp against the 718 Cayman’s 300 hp. More power helps with merging, overtaking and climbing hills, especially with passengers and luggage on board.
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The 8 Series has better fuel economy
Small gaps can still matter over time, and here the 8 Series leads 24 mpg to 22 mpg. Better combined fuel economy lowers your running costs every week, and the savings add up over years of ownership.
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The 8 Series has better highway fuel economy
The 718 Cayman lists 25 mpg; the 8 Series comes in at 29 mpg. That’s not a rounding error. Highway fuel economy matters if you cover long distances at steady speeds.
Design & Size
Engine & Performance
8 Series leads
Look at the engine & performance table and one name keeps coming out on top: the 8 Series. The 8 Series brings 88 lb-ft more torque. Electrified powertrains deliver torque instantly, so compare torque figures alongside the powertrain type. Bottom line for engine & performance: the 8 Series has the edge.
Torque
8 Series: 368 lb-ft 718 Cayman: 280 lb-ft The 8 Series’s extra torque makes it more relaxed when fully loaded or towing.
Total system output
8 Series: 335 hp 718 Cayman: 300 hp The 8 Series’s extra output gives it more in reserve when you need to get up to speed.
Fuel Economy & Range
8 Series leads
The 718 Cayman has a tough time in the fuel economy & range section, where the 8 Series pulls well ahead. Here the 8 Series offers better fuel economy. The 8 Series uses less fuel on the standard combined cycle, which matters most if you drive a lot. On fuel economy & range alone, the 8 Series gets the nod.
Fuel economy (combined)
8 Series: 24 mpg 718 Cayman: 22 mpg Official figures rarely match real-world driving exactly, but the ranking between two cars tends to hold.
Fuel economy (highway)
8 Series: 29 mpg 718 Cayman: 25 mpg The 8 Series uses less fuel on the highway, a real saving on road trips and long commutes.
Space & Practicality
8 Series leads
This is one of the 8 Series’s strongest areas. On space & practicality, the 718 Cayman falls well short. The 8 Series delivers room for 4 seats. Extra seats mean you can take more people along without taking a second car. The space & practicality verdict goes to the 8 Series.
Seats
8 Series: 4 seats 718 Cayman: 2 seats Third-row seats are often best for kids, so check legroom figures if adults will sit there.
Off-road & Towing
8 Series leads
The 8 Series does a little better in the off-road & towing section, though nothing here is a deal-breaker for the 718 Cayman. The 8 Series steps ahead thanks to available all-wheel drive. The 8 Series offers all-wheel drive; the 718 Cayman doesn’t, which matters if you face harsh winters. Anyone shopping mainly on off-road & towing should start with the 8 Series.
AWD / 4WD available
8 Series: yes 718 Cayman: no Available all-wheel drive improves traction in rain, snow and on loose surfaces.
Safety & Tech
Here the spec sheet speaks in model names and types. Compare the 8 Series and the 718 Cayman row by row in the table below.
Full Specifications
Engine & Performance
| Spec | 8 Series | 718 Cayman |
|---|---|---|
| Powertrain | Gas | Gas |
| Engine | 3.0L turbo I6 | 2.0L turbo flat-4 |
| Total system output | 335 hp (winner) | 300 hp |
| Torque | 368 lb-ft (winner) | 280 lb-ft |
| Transmission | 8-speed automatic | 6-speed manual (7-speed PDK optional) |
| Drivetrain | RWD (xDrive AWD available) | RWD |
Fuel Economy & Range
| Spec | 8 Series | 718 Cayman |
|---|---|---|
| Fuel economy (combined)EPA estimate where available | 24 mpg (winner) | 22 mpg |
| Fuel economy (city) | 21 mpg (winner) | 20 mpg |
| Fuel economy (highway) | 29 mpg (winner) | 25 mpg |
Space & Practicality
| Spec | 8 Series | 718 Cayman |
|---|---|---|
| Seats | 4 seats (winner) | 2 seats |
Off-road & Towing
| Spec | 8 Series | 718 Cayman |
|---|---|---|
| AWD / 4WD available | Yes (winner) | No |
Safety & Tech
| Spec | 8 Series | 718 Cayman |
|---|---|---|
| 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 8 Series if…
- you need more seats (4 seats vs 2 seats)
- you want more pulling power from low speeds (368 lb-ft vs 280 lb-ft of torque)
- you want more power (335 hp vs 300 hp)
- you drive a lot and want lower running costs (24 mpg vs 22 mpg combined)
Choose the 718 Cayman if…
- you already know your way around Porsche’s products
Also Compared
Frequently Asked Questions
Which is better for most people, the 8 Series or the 718 Cayman?
On the specs compared here, the 8 Series makes more sense for most buyers; the 718 Cayman doesn’t win a single measurable area.
Executive Summary
BMW makes the 8 Series, Porsche makes the 718 Cayman, and both want the same spot on your shortlist. Here’s where I land. For me, the deciding factor is that only the 8 Series gives you room for 4 seats. I’d also count 88 lb-ft more torque in the 8 Series’s favor.
The 8 Series makes sense for anyone who values engine & performance; the 718 Cayman for anyone who values the things a spec sheet can’t capture.
My pick: the 8 Series.
Personal opinion based on the data above. Your priorities may differ.