hey i have a 1990 lx 5.0 and i just put in a trick flow street top engine kit i also put in frpp 24# injectors and a 76mm c&l inlet tube with the calibration tube and my mustang still is slow i have not upgraded the fuel pump or put a adjustable fuel pressure regulator on it it has 50 series flowmaster and when i drive it for a while she will just shut off and i have to pull off to the side of the road and wait around 10 mins i have a AOD in her and when i start breaking she gets real fough at 800 rpms please tell me whats wrong with her i need your help  

Sounds like the ignition module is going bad. That to me is your sudden shut off problem, and probably the running rough problem also.  

i have a similar problem i think i was driving one night and the car just died on me had aaa replace battery and the car still wouldnt start took it home and it sounds as if the fuel pump isnt getting power it wont cycle on i tried replacing the relay under the seat no luck could it possibly be the ignition module? any help would be gratly appreciated i miss my car.