I got a Viking 2 ton back in the summer, and the truck just seems really sluggish. Combine this with the facts that it will crank forever, refuses to run hot or cold (depending on adjustments), and I hear one of the cylinders fire intermittently, has led me to believe the engine is worn out.

Unfortunately, I can't seem to ID the engine. Due to a parts kit I installed, the casting number on the transmission, and the presence of a quadrajet carb, I can tell you that it is a Chevy SBC, built around the early 60s. I looked at the block, and I believe I have the stamped numbers to ID the engine, but Google isn't being friendly about it.

12K541654 T1115CTL

If anyone can tell me anything about this engine, I will be grateful.