Technical Holley race carburetor information

Anyone familiar with this Holley carburetor? Obviously a race only application, but what numbers I found don't look like a list number.

 

looks like an old 660 center squirter, maybe 850 cfm made a lot fewer of them

 

Don't look like Holley numbers.

The carburetor is a "660 Center Squirter",
Made to run on tunnel rams, two required. Originally used in the 1960's. Yours looks like it might be an early one.

Can run by itself, but not very well, milage will be somewhat...bad .

Mike

 

I see the SK prefix on alot of Ford development stuff from the 60's. That could be a pretty special unit there.
Some google searching for Holley SK37156 seems to indicate possible List #4030, dual quad application, 427.

 

I have an 850 center squirter (list-4223) and it looks like the 660 but has the race bowls on it....

 

I agree on the 660, the quick tell tell sign is the linkage plate, then of course the funky aircleaner stud

 

There is a guy on Facebook that restores Ford HP Holley carbs and is an expert if it is a Ford application. Search for Air Fuel Spark on Facebook, he might know.

 

Thanks for everyone's input so far.

 

I would think with the skirted boosters it's smaller than a 660.

This is a 660

This is a 850.