Well, I predicted 18/26 in one of the previous threads. I was close.
I am going to give it to you as prior to rounding the city is actually 17.4.Well, I predicted 18/26 in one of the previous threads. I was close.
We recommend regular unleaded gasoline
with a minimum pump (R+M)/2 octane
rating of 87. Some fuel stations offer fuels
posted as regular unleaded gasoline with
an octane rating below 87, particularly in
high altitude areas. We do not recommend
fuels with an octane rating below 87.
For vehicles with EcoBoost engines, to
provide improved performance, we
recommend premium fuel for severe duty
usage such as trailer tow.
That's actually quite a drastic change which is very surprising. I would love dyno sheets to show the differences though, more of real world testing rather than just looking at manufacturers spec differences.I believe when Ford lists power ratings for their "performance" cars (like the ST's, Ecoboost Mustangs, etc.) there is usually an asterisked note that states the published power levels are only attained when using 93 Octane fuel. With ratings changing from 350 ft lb to 380 ft lb I don't think we have seen a final "official" communication with rating as of yet.
For the Ecoboost Mustang there is speculation that the horsepower level is reduced by 11-13%. Going from 310 down to as low as 270. Some claim that the torque is also reduced by ~ 6%, from 320lb-ft down to 300 lb-ft. Some Ford representatives have refuted this claiming that the torque stays the same regardless of octane level.
There have also been reports of reductions in fuel economy when switching from 91/93 to 87. This could be how the ECU handles boost, timing, etc changes when it sees lower octane fuel. It could also be people just applying the throttle more liberally now that there is less power.
With all that said the Ford F150 2.7 Ecoboost produces 325/375 and it is listed as only requiring 87 Octane as well.
Cobb did some dyno testing of a stock Focus ST with 87 and 93 Octane. Below around 4 grand there is negligible difference but after that the 87 Octane starts to effect power production.That's actually quite a drastic change which is very surprising. I would love dyno sheets to show the differences though, more of real world testing rather than just looking at manufacturers spec differences.
Here is a video with an Ecoboost Mustang switching from 87 Octane to 93 Octane. Without getting into driver skill, ECU adaptation times, how accurate Ford's performance gauges are, etc. we see a 2-4 tenths decrease in 0-60 times (with a lot more wheel spin) when using 93 Octane.That's actually very interesting to see, thanks for the photo. Octane ratings are always a never ending discussion on forums like these but that's pretty concrete there
From what I understand Ford has done some groundbreaking stuff with ECU adaptations. For example, if you were to try to run a Subaru WRX (which requires premium fuel) on 87 octane it would at the very least throw a code (possibly going into limp mode) under anything above a light load. At the worst there could be detonation and engine damage.That is amazing. That video needs to be put in my archives now. But I'm positive this doesn't apply to many vehicles older than a couple of years ?