Can anyone tell me what I have with these 425 head#s 1805907T--17308
also block casting #389244D It is out of a 1966 toro said to be rebuilt.

Another 425 out of 1966 toro with these #s 621971T on one head only
same casting # on Block as above engine.
still searched for the right thread and found what I needed
took a while but I got it

 

All 1966-67 425 blocks are casting number 389244D.

All 1964-67 Olds engines came with an engine unit number stamped on the front of the passenger side head (only). If the heads have ever been off the engine, they frequently get reinstalled the other way around and the engine unit number stamp will end up on the back of the driver's side head. If you have two heads that have two different stamps, they came from different engines. In 1966, the engine unit number for a Toronado will start with the letter "N", followed by six digits, then the letter "T". Only Toronado engines got the "T" suffix in the engine unit number. The Protect-O-Plate will list both the car's VIN and the engine and trans unit numbers, allowing one to match those components to the VIN.

 

factory Tri-Carb 442s had engine numbers V------T