Right, so why not compare the 66 350hp 327 4 speed which they made more of and was closer in year to the 67 Barracuda then the 65?
Looks like they had 5481 350 hp 327 Novas in 1966, powerhouse not even available with that motor, that year.
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.