How to get my escort to start?

I have a R reg Ford escort,had induction kit,and bk box fitted to it,a week later,the car stopped when i was at a set of lights,and i thought i stalled it,but the car would not start again,and since then the car has dead,it will not start,has new spark plugs,petrol and battery are fine,put the origonal airbox and exhuast back onto it,but no luck,no idea what is wrong with it,and can not afford to put it into the garage,any idea what the cause could be?