How long does 93 octane last

At fueling stations in the United States, octane is typically displayed as a number, 87 through Essentially, these numbers provide a scale to measure how much heat and pressure can be put on the fuel before it spontaneously combusts.

Spontaneous combustion is a source of engine knock which can quickly damage an engine. Octane ratings are important because different engines expose fuel to different amounts of pressure and heat. Engines must use the proper octane fuel to avoid knock and provide reliable operation. A key aspect of gasoline stability is vapor pressure. Pump fuels are limited to 7. If stored in a vapor tight container the vapor pressure can be maintained for long periods of time.

Fuel exposed to the atmosphere can lose light components within a couple of days. Over time as vapor pressure decreases the fuel can become stale.

Butane is a volatile gasoline component used to tailor vapor pressure in accordance with seasonal needs. Switching from 87 octane to 93 yielded a 7-hp gain on the dynamometer, but that advantage was lost in the noise at the track. There, the CR-V's zero-tomph and quarter-mile times both tracked a tenth of a second slower on the expensive stuff. While fuel economy at 75 mph ticked up from Honda built its reputation on a line of unassuming, egalitarian motorcycles in the '60s.

Nearly 60 years later, the company's identity is still predicated on the same sensible and modest ethic, right down to the fuel that you put in the tank. BMW explicitly warns about engine damage from doing so, and while that seemed unlikely in such mild temperatures, using the cheap stuff would have been wildly out of touch with what an owner would do at least until this M5 reaches its fourth owner sometime in BMW requires octane fuel at a minimum, with 93 recommended, so we did just that, switching between the common forms of premium gas depending on which state you're in.

Are Californians, with their watered-down premium, leaving something on the table? We wanted to know. The dyno results shocked us. Not because of the hp difference between 91 and 93 octane. No, that delta was in line with expectations. Our jaws were left hanging by just how much power and torque we measured.

While BMW claims horsepower at the crank, the dyno reports it makes that much at the wheels after driveline losses on octane premium. And both fuels produced significantly more torque than BMW's advertised lb-ft.

The higher-octane fuel trimmed a single tenth of a second across all of the M5's acceleration times. That results in a time-bending 2. The BMW also claimed the largest fuel-economy margin in the test, but the 0. The M5 Competition stands as proof that the octane rating does make a difference, although in the case of these two premium fuels, if you're forced to use 91 octane, you're hardly missing out.

At Naturally then, the Ford hauls ass as effortlessly as it hauls a half-ton of manure. Engines with high compression ratios or turbochargers often require high octane fuel found in premium gas for optimal performance and fuel efficiency. However, the majority of cars on the road today are optimized to run on regular gas. The detergent additives in your gasoline are far more important than the octane level, as they help clean your engine and optimize performance. Each retailer offers a different blend of additives, used across all grades.

When it comes to additives, some hold themselves to a higher standard. They claim that lower concentrations of detergent additive can leave more deposits on engine components, including fuel injectors and intake valves. This, in turn, can lower engine performance and increase emissions. Engines with a high compression ratio typically require higher octane fuel to achieve its intended level of performance, fuel efficiency and emissions.

Many drivers are always on the lookout for ways to cut their spending at the gas pump. They may choose to buy the most fuel-efficient vehicle , such as a Honda Insight or Toyota Prius. Trucks and large SUVs usually use more gas than smaller cars.

For some drivers, it makes sense to limit their daily driving as a method of saving money. Different types of fuel have different lifespans.