The thing with the 194 head, not the "conjoined" exhaust ones, is the chamber if smaller so it will boost compression some. So it was a cheap improvement on a stock engine. Some here feel that as soon as you start working on them you end up loosing that advantage because bigger valves have to be enshrouded and that makes the chamber larger. Some here claim there is still an advantage if you do the work right but they won't tell what that entails.
Conjoined is the PC term. We don't want to offend the people of Siam.
