The 3.5 is 365Hp Easy, why not use what's been done? The 2.3L is the second
generation of the Ecoboost I4 engine family.
For the 2.3L, it's $1800 for just the control pack, plus the cost of the
engine ($6k for a new one), most people will go with the 5.0
Coyote swap instead.
http://spartaperformance.com/2-3l-ecoboost-engine-control-pack/
It was a little easier with the 3.5L:
The oil pan on an F150 3.5L Ecoboost is the same part as the 2011-2014 3.7L Mustang.
So, there were no modifications needed for it.
The 2011-2014 Mustang's MT-82 6-speed manual as used behind the 3.7L V6 will bolt
right up to the F150's 3.5L Ecoboost engine.
The motor mounting bosses on the 3.5L Ecoboost block are identical to those on a RWD
3.7L V6 block.
The 3.5 has 6-bolt main bearings, oil cooling jets for the pistons, a forged crankshaft, forged (powdered
metal) rods and makes 365HP and 420 ft-lbs of torque and 90% of peak torque from 1700rpm through
5500rpm, on 87 octane fuel.
It could run in the 11s and get 30mpg highway in the S197s.
You need a custom air-to-air intercooler, an oil cooler, a larger radiator, modified drive shaft, etc,
even with the 2.3L, as you would with the 3.5L.
PATS is a separate module connected to the ECU, but they're paired by VIN.
The control pack may not even include PATS, it should say if it does or not.
The 3.5 EcoBoost is also as big as the 3.7, and kind of looks similar:
However:
The bell-housing pattern on the 3.5L for rear wheel drive Ecoboost is unlike
anything else Ford has ever sold, totally unique to this engine. The 2.3 was
introduced in 2015, with a more universal pattern for cross platform use. So,
you only have two models of transmission options with the 3.5. There were
only 400,000 F150s made with the 3.5L EcoBoost, but you can find them.
I think I wold go with the 3.5L personally. You can make anything fit with
money...