Me and co-workers poured over many manuals today to no avail. We could not find a match to suffix code XTA. Sorry I could not help you. If you know what kind of smog check equipment was on the engine, that might be another way for me to decipher the engine year. Also if you could provide a carburetor number, I might be able to narrow it down that way too.
Admin for Turbobuick.com
87 GN, and new toy: 1955 Chevy 3200 pickup, soon to have: 383, Cola crank, Childs/Albert 6 inch rods, Brownfield heads, 10:1 KB hypers, CompCam 284 Extreme Energy, Tilton Plate transmission realignment and built Turbo400.
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