I have been toying with the idea of putting larger valves into a 1.6 head(to make it flow more like the 1.9)
I have access to valves and seats that could be put into the head, (need to fight with the company about shipping, but thats another story)
the 1.9 head is hard to get here in the states, but I think I can get a 1.6 to flow lots better with bigger valves and aggressive porting.
what is different about the aftermarket cams, duration? timing? lift?