I was recently asked whether the 914-6 had a different air cleaner housing from the 911 of similar vintage. I had always heard that it was unique in being flatter on top to clear the engine lid. Upon checking the PET, I saw it does have a 911. part number, so I now wonder if I was mistaken. Any gurus out here know for sure?

I thought it was plastic vs metal.

For the same early '70s 911 engines, there are identical and metal but I've found that the later 911 ones are plastic, I believe.

The MFI ones are different, are all plastic, and won't work with carbs. These do not have the metal clips.

The OEM air cleaner housing on the -6 I bought brand new is plastic, not metal. Believe there may be a difference in the intake horn that mounts to the main housing.

That's interesting....mine is metal (housing, carb bases, attaching ring for the snorkel) but with a plastic snorkel and mine is original.

I'll snap a couple of pics and post tonight in case it helps any one.

This has been discussed before:

http://www.914world.com/bbs2/index.php?sho...=air+filter+box

Sorry. Not true. The early (1969-1972) 911 MFI air boxes were all metal. I'm not sure about 1973 MFI. I believe the 1973+ 2.7 Carrera RS was plastic.

- MR

Mine is plastic and think it looks just like gms has posted on the above thread as being original

We're only talking 911 air boxes, right? (It was a revelation to me that 914-6 air boxes were originally plastic, as I bought a 1970 914-6 in 1977 that had a metal air box and I assumed it was original.)

That said, I've owned a couple of pre-73 911s including a 1971 E, and they all had metal air boxes. So did every other pre-73 that I can remember looking at. I'd be very interested to learn if I'm wrong.

- MR

The stock 914-6 air cleaner is plastic.
Has a plastic snorkel that points in the opposite direction as the 911 version...both point to the passenger side.
914-6 has the holes in the plastic for the weber vent tubes.
The bases attached to the carbs are metal like the 911 ones.
I know I have some pics of both somewhere...searching>>>>

I modified a 911 metal "silencer" to use at Laguna for sound control. I was getting busted going by the sound tower because the throttle bodies air flow was crazy LOUD.

Never got to use it, but I think the guy I sold it to ("Koozy") build a nice race engine and felt this assembly did help, especially with the turbo bellmouth.

http://www.914world.com/bbs2/index.php?sho...amp;hl=Silencer

A little late to the party, but I bought mine (1088) new as well, and the box is plastic. As others said, the carb tops are metal and the air cleaner ring is metal, but the snorkel and bo

Respectfully disagree when it comes to MFI cars. My un-mollested numbers matching 72 911S MFI has all plastic box, as does my spare 73 MFI E engine.

The -6 is so modified and abused it could have had anything fitted. The box has been lost a long time ago, so a defer to higher authorities on correct -6 airboxes. At the moment it has zip loc bags on the intakes which is an improvement on what it had when I bought the car....which was nada

I'd defer to GMS as the expert on this, but to the best of my knowledge the 914-6 had plastic air filter housings, which as stated here is flatter across the top. Later MFI 911's also had a plastic air filter housing, but I don't know for certain if this is the same part as the 914-6, not sure on the dates used though.

914-6's and MFI cars did have what I call the "fire starter cold start system", which involved spraying gas down the intakes via a tubes in the air filter housing. These were disabled through a recall. Risk aside this set up is helpful starting a MFI car in cold weather.

The metal air filter housings can be made to fit, but most I've seen require some clearancing to fit, as they rub the engine lid.

I'd be willing to bet if you inspected the engine lid, or the air filter housing something has been modified a little.

Too me this sounds a lot like the old VW trick of using up stock on hand and both plastic or metal could have been correct.

There are oval window bugs out there with split window dashes and this sort thing happens all through the aircooled years.
I'm working on a 68 ghia autostick, late build date and it has some wiring components from a '69-. I had to look at two factory wiring diagrams to figure it out.

Pictures below show two boxes. The one with the snorkel is to my knowledge a correct 6 box. The one without a snorkel is to my knowledge a correct 911 box. I have the snorkel for that box, it faces the same way but has the "Y" at the end for a hot air return. Exactly what year this 911 box came on I am not sure. My understanding is it was a "latter" 911. Note though that it has the exact same squirter set up as the 914 box and also has holes for the Weber vents.

They look identical in all ways. I measured the height and they are identical. There is no part number marking on either anywhere that I could find. Same same

Click to view attachment



Click to view attachment

Fair enough. I'll readily concede to being far from either an expert or a concours judge. All I can say is I've never seen a plastic airbox on a pre-73 911, either carbureted or MFI, and I've looked at more than a few. Also, I notice you're in the UK. Is it also possible that Euro-spec cars got the plastic airboxes before cars destined for US?

Perry Kiehl is right about "fire starter" cold start for both 911 and 914-6. Again, not sure about the exact years and models, but some mfi 911s came stock with white plastic airhorns on top of the throttle bodies. The afore-mentioned cold start would sometimes dribble into the airbox. That plus a backfire plus plastic... Well, you get the picture. Not pretty. Hence, many would get swapped for metal carb airhorns. I suspect the same was also true for the airboxes.

- MR

Thanks for measuring the top part, seems it is th same. Though my original -6 has the holes for a cold starting system, one was never fitted on mine. Has none ever seen an actual cold start system fitted on their -6? I don't think any were ever actually installed.

Yap. The 1970 -6 I bought in 1977 had it. Many were disabled due to the engine fire concerns. It also had a metal airbox

- MR

We did a thread on the cold start squirters over on the originality forum. Some good info there.

http://www.914world.com/bbs2/index.php?showtopic=283855