Need help bad

[07rocket]

My car will jus shut off n then run then shut off n then run n then they next lap it maybe ok n it don't spit n sputter or stumble the fuel pump msd box n coil all fairly new 6 races fuel cell seems ok we did find loose ground on battery will that do it or what else

[Lizardracing]

Ignition switch and Master Cutoff or loose wires and terminals.

[Jeremy Queener]

fuel line closing up under pressure?

[SRXSRULE]

Ignition switch is the most common failure with a issue like this, but it could be other electrical connections too.
I wire my ignition switch to also power my gauges lights, so I no if my gauge lights are cutting in/out or flickering that i'm also loosing power to the ignition.

You could try and start the car up, then start going around to your switches and connections and slowly wiggle the wires to see if you can make it die and pin point your problem.