I'm not sure, but I think he meant the difference between a 3.8 and a 3800. If this is so, it was mainly just a different name to put on the engine cover. Yes, the 3.8 has changed numerous times over the years, but at one of those years, they just decided to call it 3800.
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Adam Smittkamp
ACS Automotive Service, Inc.
*Your ACDelco Headquarters*