I've been thinking a while... it hurt a lot at first.

i basically don't know what the potential for the engines are and I haven't decided if I want to go turb or NA, untill now i'd been thinking about an ST170 engine, which i belive is a 2.0 Duratec.
I've read somewhere it's possible to get that engine up to 250~ BHP N/A Has anyone done a Turbo for that engine and if so what's the most BHP you've got / know can be got?

Second engine i've been thinking about is the Zetec 2.0l Which I understand is a wonder ful engine but again, not sure what it can do either N/A or Turbo'd. So if any one has some rough answer's that's all good

Last but not least, I know Turbo's have Lagg and that's a bit of a down side but is there any other downsides?

and is there any downsides at all to N/A engines?

Help appreciated