well i just got my offy dp manifold and there are two different sized holes with threads on the back of the manifold right under the opening. what do those do ?? also when you hold the manifold level the opening where the carb goes is slanted, just enough to where you can only see when you hold the manifold level. also with the edelbrock 500 cfm carb what is the best set up on that.

 

Look on www.fordsix.com forum - there is a giant discussion going on with the subject being your question - good luck!

 

Not quite sure of what EXACTLY you are talking about, but it sounds like you are talking about the vacuum ports.

 

Oh - thoes are vacuum ports. For question on mounting your carb - see fordsix discussion.