Your cam is not hot. At 242/248 and only around .600" lift you have a nice street cam. My suspicion is your centerline is 114˚. With a 114˚ centerline you only have 17˚ of overlap — that is nothing to speak of.
Fast attempts to provide entry level self learning systems that can manage either fuel only, timing only or fuel and timing. FAST markets these systems essentially as plug and play up to about 650 HP. They also offer a version that is good to 1200 hp but appears to differ primarily in fuel pump volume and injector size necessary to support the higher power.
Self learning systems do well in daily driver type applications where the car is driven like a — daily driver. Performance applications do not do as well with the self learning variety of EFI systems available today. Performance applications almost always benefit from a tunable system that you have control over fuel, mass airflow or engine load and monitor a wide range of operational variables that your tuner would adjust for your particular installation.
While throttle body injectors are a convenient way to swap a carburetor out for EFI you are basically building an EFI system that duplicates a 30 year old model Detroit has long since abandoned, even for daily drivers. The throttle body injection model brings with it all the wet manifold flow and distribution issues the carbureted model it replaced had. Wet manifold systems produce significant cylinder to cylinder distribution and fueling issues that at best have compromise solutions.
FAST offers EFI systems with individual port injection and cylinder level fueling control. Other than price or visual appearance there is no reason to opt for 30 year old injection technology. The newer technology will not only run better, it will give you the ability to literally tune it to the engine size and design you have chosen for your build. Additionally there is no upgrade for this cam or that cam sort of stuff. You will however need to have the system tuned for your engine. You will spend more money than you have for your current system and you will have a much better performing engine.
Alternatively Ford's FRPP guys can offer you tunable modern day EFI systems that are among the most sophisticated management logic systems available today. Disable the TiVCT logic for the variable cam timing and you have an extraordinarily tunable system built for a n/a or supercharged environment. You specify the engine displacement in the tune and the fuel source volume and you are off to the races so to speak.
What you have right now can be made to run properly, it just takes time and effort. It will give you 30 yr old EFI performance but it will maintain a great deal of the original visuals these cars had. The modern day FAST approach or the FRPP approach will require you to go to a port injection model, not all that hard since you already have the bosses on your manifold. You could even keep the throttle body air valve to maintain some of the original car's looks.
BTW whenever you run a return style EFI system it is always to your advantage to keep the fuel pressure regulator out of the engine compartment. When you put it into the engine compartment you heat the fuel before returning to the tank and boil off the light ends. The light ends are the additives the
oil companies add to their low octane base fuel stock to produce high octane fuel. In short order it is possible to reduce high octane fuel in your tank to low octane fuel if you allow the pressure regulator to be heated in the engine compartment.
Parting thoughts, although others have already said it, the in tank fuel pumps are by far the best for these types of applications. They are quiet, available in stunning capacities and are cooled for better performance and long life by being submersed in the fuel.
Ed