I have a 110 2.25 with a stock weber 32/34 weber twin choke, I tried a SU but was not that impressed. I have since fitted a Weber 38 DGAS carb new boxed from ebay £47.00 (fitted to 2.3 and 3.0l Fords) I had to grind out the manifold to allow the bigger throttle butterflys to open but apart from that it fitted easily. I used a K&N filter with the carb rejetted the carb. The performance difference is very noticeable, the engine is a lot more free reving and torquey at the bottom end. The fuel consumption has stayed the same day to day but better on a long run. I will be modifing the head shortly with some small stem Stainless valves, porting and higher compression.
PS webcon in the US do a Weber performance kit for the 2.25 and 2.5 engine Manifold and 32/34 DGV
ALAN