The one shown posted here (in post #2) is apparently the 8BA version of the Blackstone attempt to provide a double pumper replacement pump for late flatheads.
Suspect that the one that is posted on the HAMB for sale site was never meant for "racing" but just an embellishment by the seller.
This is an early Blackstone add on double pumper for earlier flatheads (as gleaned from Ebay)
