I personly like the 1600 CVH as I raced it for 5 years in my grasstrack stockhatch. The NA lump is easy to tune from the standard (xr2) 90bhp to 130bhp with very little money spent on it just a cam , exhaust manifold and better carb(s). How ever the jump above 130bhp costs a bloody fortune and thats where it's down fall happens as the 1800 Zetec in the later XR2i puts out 130bhp as standard and the 2000 zetec E from the mondeo makes that with much more torque. I can't comment on the 1800 cvh as I've very little dealings with it but I would have thought a set of bike carbs and a four branch manifold should help it along a bit. The one thing that does appeal though is that you can make them run with just 3 live wires, how I miss coils and dizzys
