2litre zetec would drop in with minimal effort, probly a day or 2 if you've done this sort of thing b4 and could easily see over 200bhp on bike bodies with no lag or reliability issues. you'd probly spend as much getting an frst lump in and all the bits and bobs you need. depends on what you ultimately want from the car, and the other mods you've got planned, ie suspension, g'box etc. whatever you do now is a foundation for what you finally end up with when you've splashed your wad on it over the time you own it.