Paul,
I replaced my 2L Duratec with a 2.5L Omex Duratec. It produces 217bhp & 200 ft lbs of torque with a very flat torque curve. It sounds great, goes really well & is a excellent car for touring / blasting about.
It isn't a cheap option however I did have to make various other mods (suspension, LDS, bodywork etc) to compliment the engine. You wouldn't have to do these. I was also surprised how little I made on selling the old engine, however your Cosworth is significantly more desirable & should make substanciatly more. I would suggest that you do the sums to see the cost difference between 2.5 or MR11 MOG 3.7.
