Comparing the Edelbrock split log style to Ford's 4 hole crossways plenum.
The later is a more complicated (expensive) casting, if only in the plenum area, hence the popularity in the after-market manufactures of the prior.
![Wink ;)](http://fepower.net/simplemachinesforum/Smileys/default/wink.gif)
Of course the really cool part of the Ford castings' routing is that it will better accept sideways carburetor mountings!
![Cool 8)](http://fepower.net/simplemachinesforum/Smileys/default/cool.gif)
Scott.