or a decent manifold,
there are some later A14/15 manifolds that flow a treat, look a little like a GX shape, but have a single 3 bolt flange, instead of the twin pipe,
but they fit good and flow well.... i don't have the dyno sheet, but "reliably informed"

and yay for somebody posting specs for what they did to tune the carbs,

seems everybody looks for info, gets them done and nobody says what they did...