Stick with the 1600 CVH mate. Just put a decent set of pistons in it with a set of these rods and it'll take all you can throw at it. Port the head and it'll make as much power as your turbo can flow air.

http://cgi.ebay.co.uk/ws/eBayISAPI.d...MEWA:IT&ih=018

Just make sure you get the right bolts with them.

If you want massive power (as in more than 350bhp) then you're probably better looking at a Zetec but will still need to change the rods as they are not a strong point in a Zetec (like the CVH).