[GarysZ24]

Interesting what else I found when doing more research on things relative to this month. In trying to find out why the '63 Chevy Impala/Bel-Air/Biscayne wasn't allowed in stock and super stock with the Z11 Chevy 427 "Mystery Motor", I was reminded that the L88 427 was rated at both 430 & 425hp, thus meaning 425 wasn't exclusive to the 426 Hemi(the '63 Chevy 409 also had a 425hp rating). Furthermore, 401 isn't exclusive to AMC, as "The 401 aluminum heads (PN 12363408) are listed on the GM Performance Parts Web site as the NHRA-approved engine parts for the motor they were building" the 427 L88...(source, SUPER CHEVY).