octane rating and engine performance
In Texas, the minimum octane rating is 87. On a recent trip to Glacier, I noticed a lot of the fuel in states like CO, WY and MT, the octane was 85, and you had to buy the mid-grade to get 87 and abov...
Forum Discussion
ShinerBock wrote:
Here is a good video about the effects of running two different octanes in the same engine at the same time.
Dyno Testing Premium Fuel - Octane Level vs Performance - Shell V-Power
Notice how fast and often the engine is constantly adjusting timing as I stated earlier. It is even adjusting each cylinder to have its own timing depending on knock in that cylinder. BTW, VW recommends 87 octane for that car, but states that it has the ability to adjust performance on higher octane fuels as you can see in the video
That is an interesting test. So a VW owner should expect to gain 4% in fuel economy by choosing 15% more expensive fuel. I wonder how heavy the load was on the engine during the test?
