Air Filter for '73 1.7L?, hard to locate Options

[BCinSC]

Round dry element. I found one part number: STP AF103 that apparently AutoZone lists, but doesn't carry and can't order. I've checked all local FLAPS, Pelican, AA, etc. What are my options?

[type47]

Find an oil bath air cleaner

[Pat Garvey]

I have a 72 oil bath cleaner assy, if you're interested. Fairly nice & still has the facory script on it.

PM if interested.
Pat

[black73]

Champion Labs makes the STP filter. AF 103 is the correct part number for the Champion brand also. Click the link and insert zip code...

http://www.champlabs.com/content/where-buy

[markb]

Call Cap'n Krusty (John Larson). He bought the last ones I've heard of. 805 925-1993

[JamesM]

Round dry element. I found one part number: STP AF103 that apparently AutoZone lists, but doesn't carry and can't order. I've checked all local FLAPS, Pelican, AA, etc. What are my options?

I have not done a side by side compairson between the two (yet) but i can tell you that the early style 1.7 oil bath filters are pretty restrictive. I ran one on my buddys 2L with bus intake and the 1.7 oil bath and the filter wound up killing the throttle response and power. It might not make as big a difference on an actual 1.7 but i suspect that you are better off with the later style 1.7 paper element.

Last time I owend a 73 1.7 was about 10 years ago, so this is all from memory but as i recall the elements were NLA even back then. The one that was in the car i picked up was not even the correct element.

The dimensions on the AF103 are listed as: Height 3.22in (82mm) ID 4.94in (125mm) OO 8.06 in (205mm). The closest thing i can come up that might fit that you could probably get locally is the element used in a 68 bronco - SA148. K&N lists the dimensions on that filter as Height 3.25in ID 6.313 in (160 mm) OD 8.313 in (211 mm). The OD might be slightly to large though, i dont recall how much extra space was in that housing, and it will not center properly due to the ID being larger.

From what i recall, and correct me if i am wrong, the housing has a raised portion in the middle to keep the filter centered. If this is correct then I think the best match might be K&N E-3270. It has pretty much the same height and ID, it is just half as thick with a lower overall OD. Less surface area then the stock element but probably still better then going back to oil bath.
E-3270
ID 5 in (127 mm)
OD: 6.375 in (162 mm)

I just bought a 73 1.7 filter housing for testing purposes and i will find out out for sure what fits when it arives.

[ThinAir]

http://www.914world.com/bbs2/index.php?showtopic=99915
http://www.914world.com/bbs2/index.php?showtopic=103615

I did a search for +round +air +filter

[JamesM]

http://www.914world.com/bbs2/index.php?showtopic=99915
http://www.914world.com/bbs2/index.php?showtopic=103615

I did a search for +round +air +filter

I just recieved my filter housing and was able to take a closer look at it today. It is pretty close to what i remember with the ID and the height being the important dimension to match. It was actually shipped to me with a CA146 filter in it so i was able to examine it and i am sorry to say anyone using that filter element is not actually filtering the air going to their motor. While the CA146 does appear to "fit" in the housing if you examine it closely you will see it is not creating an airtight seal anywhere. On the bottom side the ID is to large and the base of the filter is not touching the inner ring where it needs to in order to create a seal. Also though you can not tell just from looking at it the element is about 1/4 inch to short to create a seal on the top when the housing is assebled. From what i can tell a large amount of the bottom and 100% of the top is open to passing air. You can even shake the housing and hear the element flopping around inside.

The napa gold 2110 element listed in the other post is a slightly better choice as its ID as least would place it on the lower sealing surfaces of the housing however its height is listed at 3" which would still make it to short to seal properly at the top.


I used a highly scientific method of stacking pennies on top of the CA146 element inside the housing until there was enough pressure to keep them from sliding off to determine the height the filter would need to be to contact the top sealing surface properly. The stock filter is supposedly 82mm high but looks like there is pressure at 81mm, which is good because all the K&N custom sizes come in at 81 or 83. I measured the useable lower sealing surface between 123mm - 145mm anything larger then that and a gap starts to open up near the air intake. The stock filter had a 125mm ID so i will use that as the realistic minimum. Also if any OD less then 8" is used the filter has the potential to be installed slightly off center, so meausing from a fully offset position the maxium ID used should probably be no greater then 132mm to insure a proper seal in all cases.

So to summarize, the ID needs to be between 125-132mm with a height of at least 81mm (and not to much larger) to seal properly.

SO...

K&N E-3270 is still looking like it will probably be the tightest seal with
Height 3.25" (83mm)
ID 5"(127mm)
OD 6.375"(162mm)
However i played around on the K&N site some more and found
K&N E-2520
Height 3.188"(81mm)
ID 5.188"(132mm)
OD 7"(178mm)
The fit wont be as snug however i think it should still seal and it is a thicker filter element. 23mm vs 17.5 mm

So far i have been unable to find any paper element that will work that is not NLA

[BCinSC]

The guy at NAPA worked hard to find as close a match as he could. The Napa GOld 2909 appears to fit will. I will post exact dimensions shortly (and confirm part number)

[Cap'n Krusty]

As Mark mentioned earlier, I have some. Two, as a matter of fact. AA also has them, but they're more expensive than mine. Mine are genuine VW.

The Cap'n

[JamesM]

The guy at NAPA worked hard to find as close a match as he could. The Napa GOld 2909 appears to fit will. I will post exact dimensions shortly (and confirm part number)

Napas site show the 2909 as having OD 9.1 ID 6.8 height 2.625 which sounds as though it would be pretty much wedged up against the housing itself. Also the ID would be to large to sit properly on the sealing surface.

The only place in the housing that has a proper surface to seal on is that 1/2 inch thick raised ring around the center, anything with an ID greater then 5.75in is going to be sucking unfiltered air under the filter, and if the height is less then about 3.2in it will be sucking air over the top of it.

[BCinSC]

Sorry, wrong part number. 2904. I.D. is good. Height isn't enough per your stock info, but it seemed snug.
Attributes
Air Filter Bottom I.D. (Inches) : 4.937"
Air Filter Bottom I.D. (mm) : 125.4 mm
Air Filter Bottom O.D. (Inches) : 7.125"
Air Filter Bottom O.D. (mm) : 180.98 mm
Air Filter Height (Inches) : 2.75"
Air Filter Height (mm) : 69.85 mm
Air Filter Top I.D. (Inches) : 4.937"
Air Filter Top I.D. (mm) : 125.4 mm
Air Filter Top O.D. (Inches) : 7.125"
Air Filter Top O.D. (mm) : 180.97 mm
Air Filter Style : Air Filter


Since all options appear NLA, is there another box I could fit to my 1.7L? I'll buy Cap'n's to see me through the short term, but then what?

[JamesM]

So the more i look into this whole filter situation the more complicated it gets. I am starting to think the specs i found for the height on the stock filter might not be entirely correct. It looks as though the sock filter element did not have a uniform height but instead had a raised ring around the ID on the top side to create the seal. I do not have a stock filter to measure but i suspect that the spec i found on the filter height was the height measured at this inner ring. The reason i suspect this is that people that have attempted to use filters that are of uniform height of the listed spec wind up not being able to close the filter housing all the way or cracking it due to the pressure. If you look at the top part of the filter housing you can see why. There are 3 raised bumps that a uniform thickness filter will be pressing against that will cause air gaps and the keep the housing from closing. I think the options here are are grind off the bumps on the housing and use a filter of the correct height or use a filter that is not as tall and make some sort of gasket in place of the ring that should be around the ID.

I found some more information as well as pics of what i am talking about here.
http://www.vwtype3and4club.org.uk/forum/vi...003e69ebcb0cce5

Intrestingly enough the fiat filter they are using as a replacement in that post is the application for the napa gold 2110 however the stock fiat filter also had a raised ring like the 914 filter where the napa 2110 does not appear to. To confuse you even more the K&N filter for the same fiat is the E-2550 although the height on the K&N is listed as .125" greater then the Napa (perhaps to help make up for the lack of sealing ring?) the K&N e-2550 is one i have been eyeing as a good possible canidate to work with.

That NAPA 2904 you found has the perfect ID and a decent sized OD as well, it might be the best canidate to work with but i suspect it is not sealing on the top side as well. If you could, put some playdough or other compressable substance like that in between the top side of the element and the housing and see how much it compresses. I am betting there is still somewhere between a 1/4 to 1/2in gap there. If we could find(or make) some sort of rubber or plastic spacer ring though i think that filter would be perfect.

[markb]

Back when I was helping out at the Krusty one's shop, we had our local Napa store do a physical search to match the filter housing, and the closest they came was a Napa Gold 2110. There may be others that fit better, etc., but this is what they came up with.

[Rod]

The K&N 1000 that I put in my 1.7l is still going strong! (second link above!)

[JamesM]

The K&N 1000 that I put in my 1.7l is still going strong! (second link above!)

Take a closer look at how the E-1000 sits in the filter housing, there are gaps all over the place.