Is 6-7/16 standard center to center dual 4's?

[pryotex]

I'm setting up to mill out a dual carb air cleaner cover for my engine. It's stock GM dual quad. Are all the duals the same center to center?

 

[Jim Sullivan]

The stock dual quad intake center to center of the carbs is 6 3/8", at least that is the measurement I've been using for years. The Edelbrock dual quad intake is the same. Offenhauser dual quad intakes have the carbs further apart. I'll check the measurement later.

 

[quik9r]

The dual quad hemi carb spacing is wider is than a 409. Jim is correct for the 6 3/8 spacing on stock intake with stock carbs

 

[pryotex]

I knew it took 6 3/8 elements, wasn't sure if they were touching. I'll check before I finish coding the program.

 

[Jim Sullivan]

Offenhauser carb spacing is 7 11/16".

 

[mr6x]

6-7/16" is correct.

 

[Iowa 409 Guy]

FYI McQuillan looks to be 9 1/16