Two significantly similar cars, no doubt about that. Still, each one has something different to offer. Having both cars powered by petrol engines and utilizing the 2-door coupe body style within the same 'Sports car' segment, the only major difference here really is their wheel drive configuration (4 x 4 for the Porsche and rear in the case of the BMW). The first one has a Porsche-engineered powertrain under the hood, a 6-cylinder, 24-valves 355hp unit, while the other one gets its power and torque from a 6-cylinder, 24-valves 343hp engine designed by BMW.

The fact that the BMW got tested by the European New Car Assessment Programme (Euro NCAP), while the other contender didn't, offers a slight advantage, as the 4-star rating is better than none. Moving further on, let's take a closer look at some additional safety-related facts. Both vehicles belong to the sports car segment, which is generally classifying them somewhere in the middle safety-wise, but that fact doesn't break the tie between the two cars. Furthermore, when it comes to weight, a factor that most people underestimate, 911 offers a marginal difference of 9% more metal.

Manufacturers have been building their reliability reputation for decades now and, generally speaking, it appears that BMW does have a slight advantage, at least on all of the models level. These are the official statistics, while our visitors describe reliability of Porsche with an average rating of 3.7, and models under the BMW badge with 4.2 out of 5. Unfortunatelly, I don't have enough insight that would allow me to comment in more details on the specific models level. We should definitely mention that owners of cars with the same powertrain as 911 rank it on average as 3.0 out of 5, exactly the same as the other one.

Porsche is a bit more agile, reaching 100km/h in 0.3 seconds less than its competitor. In addition to that it accelerates all the way to 280 kilometers per hour, 30km/h more than the other car. When it comes to fuel economy things look pretty much the same for both cars, averaging around 12 liters of fuel per 100 kilometers (24 mpg), in combined cycle.

BMW appears just a bit more reliable, although the difference is truly marginal. The most important thing when deciding between any two vehicles should always be safety, both passive and active. In my opinion, everything taken into account, BMW Z4 offers much better overall protection, which launches it ahead of the other contender. From there things take a different direction, with Porsche offering somewhat better performance, just enough to call it quicker. To make things even better, it consumps less fuel! At the end, as much as I'd like to give you a winner here, it's simply a pure tie if you ask me. In any case that's my personal view, built upon all the data available to me. What should decide here though is the way you feel about the two vehicles, and I hope you'll find my guidelines useful in the process. Also, you could use the oportunity to find out which car, everything taken into account, would be the perfect choice for you in the eyes of the virtual adviser™, out of 12.000+ vehicles we currently have in our database.