Depends. 8 out of 10 cars had 2.73
275
6 speeds came with 3.42 and the autos came with 3.23 Autos were standard 2.73. Optional 3.23 (GU5 code in glovebox)
im almost certain that they came with 3.42 or 3.43 gears stock. i know its 3.4? something automatic z28's came with 2.73 rear gear manual z28 came with 3.42 rear gear 6 speed manuals came with 3.42. Autos were 2.73 with optional 3.23 (If your shifter has PRND2 then you have 2.73. If you have PRND21 then you have 3.23)
4L60E came in 94+
My 79 olds cutlass came stock with those gears they sucked
Yes some came stock with 3.55 gears
305
An RS camaro came stock with a v6 but came had the option of a v8, turns out most RS's were v8's
3.73 gears are stock, 4.10's were available as an option on certain trim levels.
4:10 or 4:11 gears.
15in are what came stock but 16s aren't uncommon.
The 305 TBI