i would not even bother with cosworth in na form if you want a bhp figure over 180bhp as its really expensive and not worth the amount you put in for the bhp you get back, lots claim to have hit 200bhp with cosworth na form easily but truth is they have spent thousands and are only just hitting 180bhp, if i was you id stick to something simple like a 2.0l zetec silvertop, everything you need to put that engine in youe escort is on this website and im sure they will give you plenty of advise when it comes to buying

http://www.retro-ford.co.uk/shop/catalog