Fitech- New install, no start.

I don't know anything about FiTec injection but if it's carbureted you floor the pedal to clear excess fuel. If it wasn't starting, I would pull some plugs to see if they're soaked with gas.
I don't know if it is throttle body injection or port injection, but if tbi you would be able to look down the tb and see the fuel spray. If port injection you could feel/hear the injector pulse. They also make noid lights to light up when injector pulses, so you could visually see them firing off.
first thing, I'd confirm, is that you have adequate grounds for everything.
If it's tpi, how does it get its signal for timing? Did you change the ignition side of the equation?