That looks like a LT1 from a Craprice, Impala, Roadmaster, or Caddy. 330 lb-ft torque and 260 HP. Don't let the numbers fool you the LT1 has a nice wide torque band. A 4440 lb. Caprice with a LT1 will run about 15 sec. in the 1/4 mi. plus or minus a few tenths. Be sure to check that it's a 5.7L, the 4.3L looks just like it. You'll need a wiring harness and computer. Lots of info on
www.impalassforum.com. I know some forum members have TH400s.