Forgive me if this has been covered before, but do the new F-150 ecoboost engines require high octane fuel?

 

No, not really. It might run a tiny bit better on 93, but the difference will be immeasurably small. My mom's Mercedes R500 says in the book that you have to run it on 93 or you'll hurt it blah blah blah.... She's been running cheapo 87 in it for 109k and it has not had a single (engine related) problem.

 

No, not if stock. Only if you are tuned for that specific octane do you need to run it.

 

I think, and others may vary in opinion, that you'd be better off going with non-ethanol gas instead of using 93 octane. The engine will run more efficiently and you'll get better performance and mileage under the same conditions. It'll cost about the same as 93, but overall performance is better and you'll feel the difference as soon as you add the non-E gas.
Two of us have 2011 FX4 SCREWs with the 5.0/3.73 and get about 19.5-19.8 with the good stuff, and about 17.2 with E-gas. Neither of us are particularly conservative where the gas pedal is concerned.
A third co-worker has the EB/3.31 in his truck (same except XLT), and gets 23.8-24.0, but only about 19.5-20.0 on E-gas. Now, having said that, we're also running fully synthetic fluids throughout, a K&N filter, and nitrogen in the tires at 5psi over factory specs on the door labels (but under the tire limits). The only thing we haven't done so far is add a cold air intake kit. Not messing with chips/programmers, due to warranty issues.

Although the engines all specify Flex Fuel (except for the Raptor, of course), they definitely like real gas more. The website is pure-gas.org. Pick your state and locality and you'll probably find a place in your area.

Hope this helps.