pumaracing 45mm valve head which i am currently running to make the cvh head work well with the 2.0 upwards zetec bottomend, you really need huge valve area and big ports to get as much air in there as possible,
A head which might not work well with a 1.6cvh unless you ran steel rods and was able to rev beyond 7000rpm this head will work well with the bigger bore bottomend..

thanks

sean