1970 SS hoping smog is not correct because I'm anal compulsive.

How about the LS6 cars?

1968 I believe was the first year that cars came with some sort of smog equipment.
Smog pump etc.

PCV showed up in '61 in California, '63 federally. The closed PCV system was used in California starting in '66, '68 federally. Smog pumps began in '66 in California, '68 federally on open-element air cleaner V8s and/or manual transmission V8s (Chevy anyway). TCS (Trans Controlled Spark) began in '70 and was responsible for the dropping of the smog pump from all but the 'fringe' engines (like LS6 & L78, LT-1). I believe the EGR valve showed up in California in '72 (not sure) and '73 federally (for sure). Smog pumps came back with a vengance at that time.

So to clarify, 1970 LS5 with TCS and no pump, LS6 with pump and no TCS?

So to clarify, 1970 LS5 with TCS and no pump, LS6 with pump and no TCS?

The LS5 did not have the a.i.r. pump. I believe that all engines used the TCS (in passenger cars), while light duty trucks had an either / or situation. The LS6 would have used both the smog pump and TCS I think. When you run a fuel-rich carb, have a radical cam and high compression, all the ingredients for dirty exhaust are there. In view of that, the engineers threw all the emissions stuff at those top performing engines to get them out the door legally.

On 1970 Chevelles all solid lifter motors had smog equipment