"1969
400/350
400RAIII/366 (no relation to the RAII, despite similar rating.)
400RAIV/370"
This is slightly off but , here goes beating a dead horse.
I have the Pontiac sales brochures from both 1968 and 1969 early and revised additions, I found them the other day and looked up what Pontiac had in their announcements.
The 68 stuff is correct as written before.
In 69'
The engine GTO options were
400/350 HP standard GTO
400/360 HO (Known as the HO engine)
400/366HP RAIV... Originally rated as 366hp in Pontiac Brochures early on. With Arrival of the Judge this became 370HP. And the 400/360 HP HO motor with ram air in the Judge became LATER known as the RAIII. You could buy a 400/360 HO motor non ram air in either a GTO or rated lower in a Firebird.
The Only differences in any of the D-port motors was the camshaft durations, they all had the same lift. And used all of the same engine parts. The HO motors and the RAIII as LATER known used the same camshafts, but the RAIII obviously had ram air. If you were to order a 69' Judge it came standard with a "RAM AIR 400" there is NO mention of a RAIII motor.
The previous comment about RAIV's name coming about because of 4 ways to get air into the motor was correct. Until they found the system to complicated to build. It had NOTHING to do with the chronological order of 400 ram air engines.
http://www.stockmusclecars.com/68-engines.jpg
http://www.stockmusclecars.com/69-engines.jpg Again there are NO stickers or emblems on any GTO's or Firebirds designating a RA1 / RAII / RAIII engine.
Only ram air or RAIV