[unruhjonny]

I have for the past couple days been trying to figure something out, but haven't been able to hit proverbial pay dirt.

I am hoping that someone here can clarify this for me.

Regarding the dual snorkel air cleaners of 1969-1972, I have understood that there are in essence five types:

1. 1969 - regular drop, no fuel bowl vent hole, snorkels spaced out the furthest
2. 1970 - regular drop, no fuel bowl vent hole, snorkels spaced aprox 90 degrees apart.
3. 1970 - increased dropped base, no fuel bowl vent hole, snorkels spaced aprox 90 degrees apart.
4. 1970-1972 - regular drop, with fuel bowl vent hole, snorkels spaced aprox 90 degrees apart.
5. 1970-1972 - increased dropped base, with fuel bowl vent hole, snorkels spaced aprox 90 degrees apart.

I have understood that the types go something like this:

Type #1: 1969 GTO & GP
Type #2: 1970 GTO & GP
Type #3: 1970 Firebird (Formula 400; L78)
Type #4: 1971-1972 GTP & GP
Type #5: 1971-1972 Firebird (71-72 Formula 400; L78, 1971 Formula 455; L75; 1971 Formula 455; LS5)

Note: The Type #4 & #5 could be used on 1970 model year vehicles; they were used on california vehicles where the third last digit in the carburetor's application code was "5", but if equipped on non-California car, there was a rubber plug placed in the hole intended for the carburetor vent.

Is the above application correct?

I am asking this because I know a gent with a 1970 GP, and I think he has the wrong air cleaner for his car - but I believe that I have the correct one.

I had essentially understood that the dropped base air cleaners were only for the Firebirds.
I had also understood that the dual snorkel air cleaners were more or less reserved for the "performance" models (Firebird, GTO Grand Prix), while the Tempest/Lemans, and full sized cars received a single snorkel air cleaner.

Am I wrong?



Secondly;

Is there a comprehensive list somewhere for the air cleaner decal application codes?
If not super comprehensive, how about 1970-1972??

What I have learned so far from the information shared here is the following:
RM = 1970 Firebird (Formula 400; L78)
RR = 1970 Firebird (Formula 400; L74)

I am looking at an original fairly well preserved decal which is an "RO" code, but cannot seem to find this one mentioned on the forums (short of spending days combing through search hits);
I am thinking it's original, but maybe it's a thirty year old reproduction??