[dannyego]

I was told it was spreadbore but it kinda looks like a squarebore. Then again it looks a bit different then my square bore on my 56...

 

[lonewolf85]

its a square bore

Even though the secondairy throttle plates are larger than the primary that is still a square bore carb. Spread bores like the Rochester Qjet Carter thermoquad or the holley spread bore have very small primary and very large secondairy throttle plates. Randall

 

[56owner]

picture

The picture you posted is a squarebore. Spreadbore carbs have 2 small primary bores and 2 large (2.25 in) secondarys.