392 Hemi 2 X 4 Progressive???

My friend has a 392 with a stock 2X4 manifold. Should he have progressive linkage? My Wiend manifold is open so a progressive works.
I just wonder if the stock manifold is open like that?

 

Inquiring minds want to know.

 

The 300 intake I have has non-progressive linkage.

 

The 1955 300 intake picture above would benefit from fixed linkage due to the smaller seperated plenum, but the later manifolds have a very large open plenum and progressive may work better if the carbs are big. Run the rear carb as primary.

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If you use edelbrock carbs don't use progresive linkage.
I have tryd that. I drived the car with a lamba meter and that said thats were not good
It gave mutch better result with linkage that open both on same time, with out changing annything else .

 

Why would you even ask? Two fours are supposed to open at the same time!

 

Thanks for the input!

 

I run mine with progressive and it runs well with that setup. I have two 600 cfm eldebrocks.