So thats a "tape" - Think like a Dyamo labelmaker. Thats used in the casting house for a lot of in-house data. Its applied to various parts of the pattern/mold. That may tell you what cores to use, verify the type of aluminum, what the purchase order is etc. The next time the patterns are used, the "tape" is removed and replaced with another one.
At least this is the case for our aluminum and iron castings at AG
Off a high output ‘vette this is likely a Winters casting not GM. These were a contractor for Chevy high performance intakes look for a snowflake pattern somewhere on the upper exterior of the casting.