Good morning everyone,
I decided to to a little experiment with my car and see how it really performed and what would happen when I ran 89 gas in it. To be perfectly fair, I didn't take it to a dyno, so I can't give exact numbers on the HP / Trq changes, but I will state my "butt dyno" experience... I do have some interesting numbers on the gas mileage though.
First, let me state unequivocally that the car ran completely fine. No strange behavior from the engine, no rough idling, no hesitation, no overheating, etc., etc.
Second, from the "butt dyno" experience, I would say I felt a very small decrease in power when in 4th and higher. However, I could have been just imagining it. Without an actual dyno, I have no choice but to throw this out as I cannot validate any actual power loss. Again, and it is important to note, the perception of loss was very minimal.
Finally, and the most interesting, I have some data on the gas mileage. It is important to point out that I drove the same on the last four tanks of gas. That means no special or unusual trips, and I drove the car as hard or as light as I normally would. I treated the car no differently in other words.
Let me give you some numbers (based on actual miles driven / gallons. I do not use the trip computer as it has proved inaccurate) from the two tanks of 93 octane I ran before:
23.9 MPG
23.5 MPG
Now for the 89 octane:
23.1 MPG
23.3 MPG
If I average the 93 octane, I got 23.7 MPG. For the 89, I got 23.2. That is a difference of 0.5 MPG.
So let's look at this another way. If I put an average of 13 gallons per fill up, (That is when I typically fill the tank.) that translates to only 6.5 miles difference per tank!
In terms of costs (taken today as I drove past my neighborhood gas station):
13 gallons of 93 costs about $54.47 (at $4.19 / gallon)
For 89, 13 gallons costs $52.65 (at $4.05 / gallon)
So we are only talking about $1.82 price difference per tank. Or, to put it another way, I can put $1.82 more in a tank to go another 6.5 miles.
Draw your own conclusions, but to me, there isn't enough price difference to between 89 and 93 to really worry about which one I use. I suppose I will go back to 93, but I might just run one more tank of 89 through just to be sure. Then I will go back to 93 and get more data....
Thoughts?
I decided to to a little experiment with my car and see how it really performed and what would happen when I ran 89 gas in it. To be perfectly fair, I didn't take it to a dyno, so I can't give exact numbers on the HP / Trq changes, but I will state my "butt dyno" experience... I do have some interesting numbers on the gas mileage though.
First, let me state unequivocally that the car ran completely fine. No strange behavior from the engine, no rough idling, no hesitation, no overheating, etc., etc.
Second, from the "butt dyno" experience, I would say I felt a very small decrease in power when in 4th and higher. However, I could have been just imagining it. Without an actual dyno, I have no choice but to throw this out as I cannot validate any actual power loss. Again, and it is important to note, the perception of loss was very minimal.
Finally, and the most interesting, I have some data on the gas mileage. It is important to point out that I drove the same on the last four tanks of gas. That means no special or unusual trips, and I drove the car as hard or as light as I normally would. I treated the car no differently in other words.
Let me give you some numbers (based on actual miles driven / gallons. I do not use the trip computer as it has proved inaccurate) from the two tanks of 93 octane I ran before:
23.9 MPG
23.5 MPG
Now for the 89 octane:
23.1 MPG
23.3 MPG
If I average the 93 octane, I got 23.7 MPG. For the 89, I got 23.2. That is a difference of 0.5 MPG.
So let's look at this another way. If I put an average of 13 gallons per fill up, (That is when I typically fill the tank.) that translates to only 6.5 miles difference per tank!
In terms of costs (taken today as I drove past my neighborhood gas station):
13 gallons of 93 costs about $54.47 (at $4.19 / gallon)
For 89, 13 gallons costs $52.65 (at $4.05 / gallon)
So we are only talking about $1.82 price difference per tank. Or, to put it another way, I can put $1.82 more in a tank to go another 6.5 miles.
Draw your own conclusions, but to me, there isn't enough price difference to between 89 and 93 to really worry about which one I use. I suppose I will go back to 93, but I might just run one more tank of 89 through just to be sure. Then I will go back to 93 and get more data....
Thoughts?
