[jhein]

Very informative and interesting article about the SD cam from Rocky Rotella.

https://www.pontiacv8.com/blog/2022/...320-k-camshaft

"McCully shared that the SD-455 with the 308/320 camshaft was compliant with the EPA’s 1973 federal standard, however, it was unable to meet GM’s internal standard. Pontiac was forced to delay the SD-455’s release until engineers could find a solution and recertify it. With customers anxiously awaiting the highly-publicized mill there simply wasn’t time to develop a new camshaft. McCully and team had little choice but to grab the closest proven performance option—a 744-spec camshaft with 301/313-degrees of duration and .407-inch valve lift. The number 493323 (stamped “Y”) camshaft was created for the application, which consequently impacted power output. "

So was the 308/320 cam the "041" profile cam? That's interesting that Pontiac held itself to a more restrictive standard than the feds. That would have been something if they put the 041 in there.