1966-67 Chevelles axle ratio with 396 and A/C

[jeffschevelle]

I have heard many people say that all 1966 and 1967 Chevelles with 396 and A/C had a 3.07 rear axle ratio as standard. I have also heard it said that the 3.07 was "mandatory" with A/C (could not be changed by ordering an optional ratio).

The power teams charts for 1967 Chevelles bear that out. Every revision has a separate column for A/C which shows 3.07 as the std ratio for all 396's with A/C, and no available optional ratios.

I always assumed that that was also true for 66's, having heard other people say it so many times. However, I cannot find anything like that in any of the original 1966 Chevelle sales literature. There is no mention of a different std ratio (or of limitations on availability of optional ratios) for A/C cars. And the description of the A/C option content does not say anything about the axle ratio, and Section C60 in the 66 AIM does not indicate an axle change was part of the A/C option.

Does anyone have any reliable info or original documentation suggesting that 1966 Chevelles with 396 and A/C came with a 3.07 rear?

Thanks!