another carb ??

[dodgedifferent2]

any idea?
the numbers i have found on the carb
5157 on the throttle plate
5275 and 5271 on the metering blocks
also on the one metering block has 4100

I am at a loss for what it is :hmmm:

 

[68R/T]

Proform Racing Series, (no choke baffle), Vacuum Secondary,


Available in either 650 or 750 cfm. New retail $525 - $585. Very desirable race carb. Although some idiots try to run them on the street.:doh: The Proforms are basically an upgraded Holley. Some common defects improved. Also, the Proform cfm ratings tend to be a little under-rated. That 650 may be in actuality more like 700cfm.

To tell which size this is check the throttle bore sizes. If there's a slight difference, it's a 650. If all 4 are the same size it's a 750.

 

[dodgedifferent2]

ok good to know
will do some measuring.
with about 40 thou difference would make it a 650