[John V.]

I have been searching for a correct air cleaner for my '73 TA. This is strictly a driver and prices I've seen have been way too rich for me.

The pix attached are supposedly from a '74 TA. It looks rough but if it is correct, I can live with it.

I have looked thru this thread:

http://www.forums.maxperformanceinc....d.php?t=699820

HFR posted some great pix of '73 and '74 bases.

But I can't tell if the base in my pix match.

Also, all the lids I've seen for the '73/'74 TA are domed. This one is not.

HFR indicates that the lack of a lid is a red flag.

Is the lid in my pix a deal breaker or is the base correct and lids are available?

Help greatly appreciated.

[unruhjonny]

here's my take
when installed 99.8% of the people out there won't be able to correctly differentiate any 1973-1978 'wide snorkle' Firebird Pontiac V8/4bbl air cleaner base;
- they all have the same snorkle to connect to the fender ducting
- they all use the same OD base
- they all use the same dropped base
the only differences are:
- the location of the fuel bowl breather "chimney"; 1973/1974 is in a slightly different spot than 1975+
- the exact shape of the dropped rounded area - the curvature seemed to alter slightly from year to year...

I don't think I could tell you the difference of one against another - the only cue I would use is the amount of "stuff" attached to it.

the upside here is that one you nail down being able to positively identify the correct one for your car, odds are you will be able to find someone who will simply swap air cleaners with you...

I just read the linked thread and thought that this was the key post:

Originally Posted by Held for Ransom

With the holiday tomorrow and it being too hot to do anything too strenuous, I thought I'd revisit this. Please correct with exceptions. For people shopping eBay, learn here on what questions to ask...

4 barrel Firebird/Formula/Trans Am base will have almost no gap (approx. .16”(1 dime and 2 pennies)) between center hump and straight edge when you lay it across the top. Sensor and carb. vent hole should be across from, not next to, each other.

1973
Has three welded clips for vacuum hoses.
Hole for screw to hold fresh air duct is circular and only on top side.
Sensor is black.
Air flap pin exits to the right.

Trans Am PN decal (Keep your GM car all GM) is located between snorkel and indent.
Measurement between snorkel and air breather hole is 15”.

Formula PN decal (Keep your GM car all GM) is located between air breather and indent.
Measurement between snorkel and air breather hole is 14-1/2”.

1974
Went to four welded clips.
Sensor went to painted black.
Air flap pin exits to the left.

1975
Hole for screw to hold fresh air duct went oval on both sides.
Added a hole in side for vacuum switch.

it looks to me like that 'air flap pin' exits to the left...
i like the fact that that aircleaner seems largely void of hte other stuff, but that emissions device on the back has me scratching my head.
The retaining ring is correct for a TA, but the lid is obviously non-TA - the correct lid should be the small diameter rounded unit - as opposed to the latter flatter unit.

[thepontiacman]

the third picture shows a base . It has a vacuum port in the back pass rear, so it is a 75 or newer.

The TA shaker bases have a smaller lid that goes over the air filter element only.

Good luck with your search. I may still have pics of the original base off a 74 TA.

thepontiacman@yahoo.com

[John V.]

Thanks unruhjonny. I did rely on what HFR posted.

I asked the seller to check the dimension between the hump and a straight edge laid across the top edge. He reported it was raised about 1/2" at the hump (if I understood HFR, it should only be 0.16" or less than so I passed.

If I understand you, every '73 4 bbl Firebird used the same air cleaner base as the '73 Trans Am?

Was the domed lid used on any other '73 Firebird or only the TA?

Assuming the lid was TA only, if I find a '73 4 bbl Firebird and snag the base, all I'll need is to get the lid? And the lid is reproduced, right?

[John V.]

thepontiacman, thanks also for your input too. The listing said '74 but when I asked questions about the dimensions, he said it might be from a '75. No sweat, somebody else snagged it.

And I gather the '73 (or '74) should not have that vac port in the back, good to know.

I think I have a better idea what I need to look for now.

[Held for Ransom]

It has a flat spot (but doesn't look like there's a hole there) next to the sensor holes. Plus, there is a vacuum sensor hanging off the side, nipples pointing down. My guess is it's later '75, possibly an early '76 unit. If there was the Keep Your GM decal on the side, it would probably read 8994001 or 8994002.

[John V.]

Thanks HFR.

Can one of you guys confirm that ALL '73 4 bbl Firebird bases are identical to the '73 TA base?

[unruhjonny]

Originally Posted by John V.

... If I understand you, every '73 4 bbl Firebird used the same air cleaner base as the '73 Trans Am?
...

Please keep in mind, I am no expert;
I posted what I seemed to observe - HFR's post seems to spell out hte minute differences between TA & Formula bases...
To me the multi-lines dealy-bob on the back of that aircleaner seemed to put it as later than 1973.

[Held for Ransom]

John, I can't confirm or deny. I had a '73 F-body 4-bbl air cleaner that was marked as a TA (it didn't have a lid). I also had a '73 F-body 4 bbl. air cleaner that measured the same as the TA unit (except Keep Your GM decal was in a different placement) and it had the decal to identify it as a HD air cleaner unit.

Remember, the '73 and '74 air cleaners will have a circular hole in the upper section of snorkel end, as opposed to an upper and lower oblong hole in the '75-up units.

[Bentwheelbob]

HFR is certainly the expert, but if this is truly just for a “driver” car and absent forensic analysis doesn’t appear wrong then move forward. That said, the lid is wrong and should be smaller diameter than the base and domed.

The top post clamp holding the exhaust pre-heater elbow to the air cleaner base should be date coded and looks original. Check it. They are date coded by quarter and the last two digits of the year.

[John V.]

Bob, you may have misunderstood my OP.

The pix I posted were for an Air Cleaner I considered purchasing IF it would fit correctly in my '73 TA. It isn't one I already own.

From everything I could determine, it not only was not a '74 TA Air Cleaner as advertised, it does not appear to have had the proper "drop base" suitable for a TA so I passed on it.

Based on the older post by HFR, the distance between a straight edge laying on the top of the base and the "hump" should be about 5/32". The one advertised measured about 1/2" according to the seller.

My TA doesn't have an Air Cleaner. As much as I'd love to move forward, I still need an Air Cleaner! And because I'm a bit anal, I'd like it to be as correct as possible.

I just spoke to a guy who was selling an Air Cleaner that he pulled out of the trunk of a 4 bbl '73 Formula. He believed it to be original to the car so advertised it as a '73 Formula Air Cleaner.

I had him measure it and he came up with 1" between the straight edge and the hump. So that put that one out of the running.

HFR, I had picked up on your description of the single snorkel screw hole previously so I'm up to speed on that detail

Also the hose tabs welded on the bottom. And the air flap pin orientation.

When I talked to the guy about the possible '73 Formula Air Cleaner I had overlooked the difference you mentioned between the TA and Formula air breather hole.

But since the hump drop dimension seemed wrong for a TA, it hardly mattered. I did ask him to check for the 3 welded tabs but he misunderstood and counted 3 vac holes. Not sure what that would represent but didn't seem like his Air Cleaner could help me.

So the search continues!

[Held for Ransom]

John, I'm posting a picture of a '73 non F-Body 4bbl. air cleaner. As you see, the sensor is close to the carb. vent hole, F-Body is opposite. It also has the pin going in the same direction and the one round hole in the upper snorkel end. No clips on the underside (sorry, no picture). Plus, the approx. 1" from the flat by the vent hole and the top of the air cleaners' ridge.

[John V.]

HFR, thanks! These details are very helpful to me.

[Held for Ransom]

http://www.forums.maxperformanceinc....d.php?t=755663

John, I also found this thread that I posted in. Hopefully, it will help some.

[Held for Ransom]

Looks to be a '74 air cleaner on eBay now.

http://cgi.ebay.com/ws/eBayISAPI.dll...m=263727847969

[John V.]

Originally Posted by Held for Ransom

Looks to be a '74 air cleaner on eBay now.

http://cgi.ebay.com/ws/eBayISAPI.dll...m=263727847969

Thanks, that probably would have worked for me but I already scored a better deal on what I believe is a '75 (has the oval holes, unlike the single round one). Included all the same extras plus the piece inside the base that looks to be missing on this one. About same condition.

Unless and until somebody wants to trade me for a '73, I'm good with the one I bought.

[Held for Ransom]

So, you'll egg-shape the carb. vent hole area so the air cleaner sits correctly?

[John V.]

Please 'splain. You're talking over my head with that one!

[Held for Ransom]

It's what led me to be measuring where the breather filter hole was in relation to the snorkel. In '75-up, they moved the vent stack on the carburetor. So, if you're using a '73 carb, the air cleaner will be "pointing" at a different angle than if using a '75-up carb. I can't say for sure where the tube will be pointing in relation to the square hole for the breather filter.

[FASTASSBIRD]

Which one has four metal tabs weld d to the bottom? I have one of those


Sent from my iPhone using Tapatalk