Air Cleaner Question and Intake Manifold Vent?? (with photos)

Hey Guys,

I have two easy questions for you.

1. I have the stock air cleaner setup on my 68 Mustang Automatic with Autolite 1100. I don't mind the stock air cleaner look but I am curious about changing to the chrome air filter as shown here: https://www.vintageinlines.com/product- ... ir-cleaner

What do I do with the oil cap? Do I just replace it with something like this: https://www.vintageinlines.com/product- ... in-oil-cap

Will this cause any performance issues? Not sure I want to change would just like to understand.

2. I am having trouble finding out what the line coming off the intake manifold is, (the steel hose). Can anyone explain that to me?


PS some pictures are old.

Save that old tin! somebody wants it.
most(some aftermarket)air cleaners have a knockout for breather/pvc,Route pvc to intake,breater cap to hole put in air cleaner.
Kind of a pre 71 smog thing,still better than a road tube.
steel line looks over-sized,but I'm guessing you have an auto. and that is going to shift modulater...
Ok,now the other guys will jump my old backside....

Hook up your pcv. Get a Spectre oil cap push in oil fill breather. Get a K&N air cleaner for full flow.

chero1369":15al1d0m said:

Save that old tin! somebody wants it.
most(some aftermarket)air cleaners have a knockout for breather/pvc,Route pvc to intake,breater cap to hole put in air cleaner.
Kind of a pre 71 smog thing,still better than a road tube.
steel line looks over-sized,but I'm guessing you have an auto. and that is going to shift modulater...
Ok,now the other guys will jump my old backside....

Click to expand...

Nope, I'm with you! Matter of fact, I'd keep the original tin ON the engine - I really doubt the chrome one actually flows more on a stock engine, and I like the look of a clean original.

MustangDadDrake, I rotated one of your photos and added colored arrows to point out some things.
You DO need a working PCV, your engine will thank you, your oil will thank you, etc. The PCV valve in the rear rocker cover (red arrow) goes to the manifold (red arrow), and if you want to use a chrome air cleaner, you'll route the hose from the breather cap to the bottom plate, usually there's a knockout - that way, the PCV system pulls filtered air into the crankcase instead of whatever dust is under the hood.
The orange arrow is what I assume you're asking about - and I'm pretty sure that's for a transmission vacuum modulator, as chero already said.
The green arrows - the one on the carb is coming off the Load-O-Matic Spark Control Valve (SCV), and should go to the distributor's vacuum advance can. The other green arrow is pointing to what I would assume is straight manifold vacuum line, usually for a NON L-O-M system, and they are NOT compatible. Makes me wonder where it goes -hopefully not the distributor?

Can't use tin because of headers and combo 32/36 and 2100 and trial heat shield.

Thank you all as always for the great feedback.

I should of posted a more updated photo. The old ones were just really to show the air cleaner. The PCV is hooked up to the carb and I have the proper carb non-scv for my non-lom. You guys have already straightened me out on all of that. I just took the attached pictures tonight. The green arrow shows were my PCV connects to the carb.

Thank you for letting me know that the line is called a transmission vacuum modular, I will do some googling and reading in my shop manual on that. And yes I do have an automatic.

If I am following this correctly, replace the black oil cap with a fully closed one and slap on the KN air filter.

I have seen the housings posted for big bucks online but I will probably hold on to mine.



I spy a steelers football.

"...replace the black oil cap with a fully closed one and slap on the KN air filter. ..."
Only if U wanna get rid of (the suggested) Closed PCV System. We 'recirculate' - frm Pvc to Carb base, from front VC to A/C housing.
As said, we went thru this B4.

Some drop the fnrt as U indicate. No 1 should drop the rear 1.
A closed frnt cap means reduction of curculating air. An open one w/a spun filter at least duz not restrict the air to help citculate up thru the pvc. (I'll leave out windage trays'n sump baffels 4 now). But I'd rather the A/C Housing 'connection' too.

No worries, ur not gunna blow it up ! Its just a good better best kinda thing. These old motors aren't great for the enviornment either...I like to use the technology as designed or improve it.

Yes sorry I meant to say a breather cap for the oil cap, as Bill suggested.

MustangDadDrake":28o9j2b8 said:

Yes sorry I meant to say a breather cap for the oil cap, as Bill suggested.

Click to expand...

Yup, you want some sort of filter on the oil cap, to let air through but keep dogs and small children out of the crankcase.

I'm not a fan of K&N filters, given their price and dubious filtration (not much when clean). You can get a dozen good 14" x 3" paper filters from rockauto for less money, and they're big enough they won't restrict flow until they get really funky.

MustangDadDrake":yw4w9srw said:

I spy a steelers football.

Click to expand...

I do too, hahaha!