Bionic Man wrote:
Nice. So, you are going with the "I had a guy tell me" theory. Reminds me of someone else on this forum......
Did the "Ford engineer" you spoke with put that in writing like the link to the owners manual?
Actually no this was at WTS(The Work Truck Show) where my company was releasing our new CNG units for medium and heavy duty truck applications. Ford is one of the sponsors of the show and they also had their engineers there to answer questions on up-fitter specs with fleet owners and up-fitters.
What he said was just about exactly what the manual stated(which you posted above) and Pickuptrucks.com stated which is that the engine was designed to run or regular at all times but if you want best over all performance(i.e. more power) then run 91 octane. The added power will be most noticeable when pushing the engine hard like towing. He stated that I didn't have to run 91 when towing or pushing the engine hard because the engine will pull timing and save itself it it began to knock real back. The recommendation for premium is for added power only.
He also said the reason why they did this is because they didn't want fleet customers to feel that they had to run premium fuel. Since advertisement regulations require them to advertise the SAE power rating at whatever fuel they recommend, they posted the 87 octane power numbers instead of the 93 octane power numbers like GM does.
Bionic Man wrote:
Plenty of people talk about using the 6.2 with standard octane as well. Compare apples to apples. Which is what the manufacture recommends in print. Which is in the owners manual. Which is premium fuel for both the EcoBoost and 6.2.
Again, it doesn't say you have to run 91. It just states that if you want more performance(i.e. power), then run 91 and it will bump up the engines power output just like PUTC stated. The truck is designed to run at 87 just like the manual stated, but will have more power than the advertised power rating on premium.
GM on the other hand is the opposite and is designed to run on and its power numbers are on premium fuel which is why it tells you to use premium. However, if you don't use premium then there will be reduced performance, reduced fuel economy, and potential knocking or engine damage. This is exactly what both owners manuals state.
