How much of a budget do you have?

If you want to keep up or even beat the cossies go for a Grp4 Escort with a BDG in it Or you could get one that looks standard drop in a 2.4 N/A Cosworth engine on injection use the cossie box with a baby atlas axle. Or even better try
Ford / Cosworth YB specialists
Millington Racing Engines
Lower Cockshutt Farm
Chetton
Bridgnorth
Shropshire
WV16 6RF

Tel 01746 789268
Fax 01746 789692
They make a 2.5 turbo unit think it is about 600bhp.