Originally Posted by DoubleVision
I don`t know why that comes up so much. Even so the Edelbrock performer is a Spread bore design, it has dual bolt patterns to accept both Square and spread bore carbs. A holley or Eddy carb will bolt right on and it don`t need a adapter plate. All it needs is the thin metal plate inbetween two gaskets that assures it covers the opening where the plenum spreads out for a spread bore carb.
Bore pattern looks different to me. Here is a link to the manifold I have