Not an equal comparison.
The 1966 327/350 HP 'L-79' would be too much for the 1967 '383-S'.
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Regarding the 1967 Barracuda '383-S'.
The early Sales Brochure states that >
{Optional Gears} 3.55 and 3.91 were available for the 4-Speed.
3.55 Gears were available as an 'option' for the Automatic.