Originally Posted by aschrager
If I remember correctly. Octanes don't mix. So that means you are using 93 some of the time and 89 the rest of the time.
But I heard that many years ago and it may not be correct.
The grades mix quite well. In fact, that's how you arrive at your mid-range grades - simply a blend of premium & regular. Most of the time they're mixed at the pump but can also be done so within the delivery tanker itself.