Can Anyone help decode a motor that I have had for years? The block serial numbers are 2780930-340-5. I was told that it is from a AAR Cuda but I don't know for sure. Thanks

 

While it is a 340, it's not a Trans Am version. To narrow it down further, check the number stamped on the front of the block, below the cylinder head on the driver's side of the engine. With that number, you can determine the engine build date.