Whatever your Owners Manual calls for. I have a '94 LT1 and a '96 LT4 (with over 193k miles, stock) and use Mobil1 exclusively - that's what the sticker under the hood says and it's obviously worked.
How is your car driven?
Don't spend extra $$$ on a motor oil if you don't spin your engine above 3000 RPM. Daily cruiser or weekend tourer, regular 5w30 is fine. Ask the previous owner what he used, then stay with that if the engine runs fine. If less than 3000miles/year, change oil and filter annually. I prefer Wix filters myself, just stay away from Frams.
There's a lot of variables here...the main thing is don't be talked into spending more money for oil than you need.
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1973 Mille Miglia Red LS5 - SOLD
1981 Dark Claret Metallic - SOLD
1982 White
94 Torch Red LT1
96 Dark Purple Metallic LT4
02 Black Convertible - SOLD
03 Millennium Yellow Z06
09 Atomic Orange Z51