Direct Connection 340 block 1971
TA blocks were the original HD/race blocks before X-blocks came out late in the '70's(?), around or after W-2 heads. However, Direct Connection did sell blocks through their program which may have been production blocks. But the only difference from the factory OEM blocks appears to be "stress relieved". It's been almost 50 years but I bought one through Massey Chrysler Plymouth on Beach St. in Daytona Beach, FL. (Note the prices!) However, I don't recall it having any TA or X-block features. Based on the catalog wording/descriptions, I would think the 340s were a factory blocks along with the others. I suppose that the OP may have one of these. But I can't think of a way to prove it without documentation, features or part numbers on the block. Either way, it would be another OEM part assigned a P-part number and sold by DC.
Same listing in 1977 but Nov. 1979 shows the "NEW" race block with 2 or 4 bolt mains and the rest of the blocks listed as "production".
Glidden probably got the first ones.
1976 catalog:
TA blocks were the original HD/race blocks before X-blocks came out late in the '70's(?), around or after W-2 heads. However, Direct Connection did sell blocks through their program which may have been production blocks. But the only difference from the factory OEM blocks appears to be "stress relieved". It's been almost 50 years but I bought one through Massey Chrysler Plymouth on Beach St. in Daytona Beach, FL. (Note the prices!) However, I don't recall it having any TA or X-block features. Based on the catalog wording/descriptions, I would think the 340s were a factory blocks along with the others. I suppose that the OP may have one of these. But I can't think of a way to prove it without documentation, features or part numbers on the block. Either way, it would be another OEM part assigned a P-part number and sold by DC.
Same listing in 1977 but Nov. 1979 shows the "NEW" race block with 2 or 4 bolt mains and the rest of the blocks listed as "production".
Glidden probably got the first ones.
1976 catalog: