This Holley carb listing verifies 210SC's info:I think it is an 850 double pumper in the early 70s for a 427 chevy dual quad set up. Might have 1:1 linkage.
Not a bad find if it fits your application.:tu
obviosly drag racing edelbrock 2*4 high ram probably for pro stock big block. trade it for something in the 600cfm range NO bigger than a 650 for low end .This Holley carb listing verifies 210SC's info:
1970 Edelbrock Hi-Perf., 427 Eng. 2 x 4
Bbl. 850 CFM