I'm just curious if anybody knows why there is a stated 5 horsepower difference in the rating of the 1966 L36 (390 horse 427) and the 1967 one. Is there any differcence at all really?
Carl, are the part numbers for the heads and cam different between the two years? Buick was bad for playing with HP and Torque numbers. In 1970 the Stage 1 GS was rated at 360hp. A non Stage 1 455 in a Riviera was rated at 370HP!