the other day i bought a quadrajet for only twenty bucks from a guy and im not sure how to identify what year and what size it is. I have 4 of them but i went and bought this one because all the other ones have all that computer s*** in the

 

look on the driver's side pad. there will be numbers going vertically.

usually 1708xxxx or 704xxxx

Then after that there will be a few letters and a 4 digit code.
For example:
1168= 116th day of 1968 or 1978
0910= 91st day of 1970 or 1980
3442= 344th day of 1972 or 1982

 

The 4-digit date code is as J-Chicago told you. That tells you when the carb was built, which could be years after it's intended usage if it's a service replacement.

The model year is encoded in the part number. It's the fourth digit if the part number starts with 7, the fifth digit if the part number starts with 1.

Note that, if the carb is old enough, sometimes the leading 70 is left off the part number stamping.

With the exception of just a few part numbers (for Pontiac, I believe), the throttle bores of all Quadrajets flow the same. When an application required a lower flow rate, Rochester built the carb so that the motion of the secondary air valve was limited. But this is easily modified, so you can make any Quadrajet flow as much as any other.

 

there were also the 702 and 1705 series...


bill