Thanks for all the reply's everyone. I know California is something else when it comes to smog. I just do so little stuff as compared to some of you therefore I'm not fully in tune with everything single thing. To confuse matters, I had a 69 Chevelle with a 307. It wasn't required to have a smog pump. That's 2 years later and the replacement engine for the 283. Make up your mind California.
There are lots of ways to reduce specific types of emissions...and the gummint never really specified what equipment car makers had to use, to meet the specs. So some cars got AIR pumps, some did not.
The 2 1/2" isn't necessarily for this 283. One never knows what's coming in the future. So since I have to graph from split dual's of the L6's mufflers forward any way's.
This is why we had books that went by year, make and model as to what each one was equipped with from the factory. A lot of the time the tag/sticker was gone or modified, you have to be accurate when doing a emissions test and back then California was all over the place emission wise.
As for the one year only thing........ This statement is not factual. Might be on the interweb, but the real car's have showed the fact's. We've delt with the process. This is Chevy/Ford,etc....... We didn't have out of state cars then, so- we had to make sure all our crap was complete to pass the emissions test. This was for 66 cars.......... I had one with a 283, built at the Oakland plant,and it came with all the A.I.R goodies.
It might have been on the A bodies in 66, my basis is on first gen Camaro's as I specialize in those cars particularly, which that pump is a one year only pump. You rarely see them come up as the LA plant for the F body was such a small percentage of total production that its rare to see 67's with the air equipment installed.
Root, back when I was into SBC's The motor that tickled my fancy was the small journal 327. When it got tired, a drag racer snapped it up. Damn thing was quick.
Once again, thanks for all the early info provided per my original question on this thread. This 283 will be striped to become near 1956 as it can be but more importantly H.A.M.B. friendly. No more info is required.