Almost free-high flow GM truck air filter
 

:cool: I found a couple air filters off GM trucks that are a lot larger than ours and fit on 4bbl qjet & others.
The 2.25" small one is off our trucks up to 72. Notice how small the inlet hole is also.
Next 3.25" is off a 73+ GM truck. The inlet is also much bigger.
The last one is 5.25". I found one of these big ones in the back of a late 70s-early 80s truck in wrecking yard...no engine, so I am not sure of the application, but it was $5. Then I found another at a swap meet with a K&N filter all for $10. Still don't know exactly what they came on, but see, they are almost free, when you find them. My 79 454 dually only came with the medium sized one, but It is getting the bigger one!
I put the medium sized one off my 454 on a 402 I am driving.

Re: Almost free-high flow GM truck air filter
 

The medium & big ones had a flex hose that brought fresh air in from the radiator support area.
Look at the inside of the big one. Some of you smarter 73+ guys are going to have to explain this one. It looks like a double filter, but the inside one does not go all the way to the top lid???.
I thought someone added it and it may be restrictive, so I pryed it off on one of them. It was just glued in. It looked like it was metal screen on the outside with ground up charcoal inside. Make any sense? What is it? What does it do?

Re: Almost free-high flow GM truck air filter
 

Frank - IIR the tall one MAY be diesel. I have seen some of the tall ones and think they may be later model diesels.

Re: Almost free-high flow GM truck air filter
 

That large one is what my '85 C10 had on it. That metal screen on the inside is some sort of spark arrestor. Your right it's glue on and when I took mine off it seemed to breath much better. I still like the looks of the early smaller ones for our trucks though.

Latter Tom:)

Re: Almost free-high flow GM truck air filter
 

Could the larger one have been on the tall deck big block C50 and up trucks? Seems to me as tho that would look right at home on the top of those motors...

Re: Almost free-high flow GM truck air filter
 

the po already instaled one of the tall ones on my 71. i was thinking of going one step further and making it a duel snorkel. my guess on the inner element is that it was a silencer of some sort but just a guess

Re: Almost free-high flow GM truck air filter
 

i have the middle one on mine but i fliped the lid upside down

Re: Almost free-high flow GM truck air filter
 

I was thinking the big`un looked like a med.duty app.,like a 366.I like the idea of one of these on my 4wd.

Re: Almost free-high flow GM truck air filter
 

My Dad's all original 1985 Suburban has the big air breather on it. I have the stock type on my truck with the snorkel cut off about 1.5" from the breather. The diesel breathers are completely different if I remember right, been awhile since I've seen an 80's GM truck with a diesel.