GM edicts in the 1960s

[442w30]

We've read a lot about the 400cid limit through 1969 and the no-racing ban from 1957/1963, but what about the 10llbs/hp rule?

I don't think I've ever read about where and when this came from.

Does anyone know?

I recently read that this was something starting around 1967, but I am not sure why other than to be for the same reason why GM got out of racing - to hedge itself against anti-trust scrutiny.

Thanks!

[old5.0]

67 is an odd year at Chevy. Massive drop in L78 Chevelle sales, L79 Nova sales fall to practically nothing, no 425 horse big cars... I imagine the internal political situation was something to witness firsthand. Governmental pressure seems the most likely explanation, but why did things return to normal, more or less, for 68?

[442w30]

I have read that the L78 was released later in the year, much like the L79 Chevy II - not sure if that's true.

Yet the L79 Chevelle skipped '66 and was back for '67, now rated 25 horses less so as not to encroach on the 396's territory.

The missing L72 is a head-scratcher because the big cars didn't seem to bear the wrath of any edicts.