the 402 is to the 396 (Hollander lists the change as late '69 model year)
as
the 400 is to the 383
I kinda disagree with this, but only for this reason:
All engines experienced a natural progression of cubic inches. The BBC started with 396 and went to 427 and 454. The 402 in between that sequence may or may not have been for some emissions reason, but notice the increase was marginal.
Compare it to the B engine, which went from 350 to 361 and 383 and 400. Notice the last leap was 17 cid, which was not insignificant.
This site (
http://www.chevellestuff.net/1970/70ss.htm) suggests engines under/over 400cid had different emissions regulations, and tweaking the 396 to tip over 400 may have solved the issue. But what was the issue?
Regarding the OP's query, I don't have the article in question, but let me offer an opinion that
Hemmings is wrong when talking about Chevelles and partially correct when talking about the Camaro. For most of the Chevys, the model year began in Sept, but the Camaro was delayed into the beginning of 1970. Hence, 1969 Camaro production was extended into November or December 1969. I would think these cars built in August through the end of the year came with 402s.
Wanna hear something confusing? The 402, as optioned in Chevelles that were not SSs, was called the 400. So there was a 402 that was marketed as a 396 AND a 400 (and, no, not to be confused with the 400 SBC)!
