Topic: 1968 S code - Air Cleaner Lid Gasket - different?

[mungus]

It seems none of the replacement air cleaner gaskets on offer cover the 68' 390. They are available for every other models, one for the 6 cyl, all other V8's and the 67'390. But nothing listed for the 68' 390.

So in the absence of other 68 lids to compare it to, is the lid different on the 68' 390 to the 302's? Looks the same to me in photos etc...
Are the lids slightly bigger or something?

Not that its a biggie, I can just use some 3M weather-strip I suppose...

[J_Speegle]

Looks like (based only on the limited info I could quickly find in a couple of books) that the dia is different by 1/4"  (smaller)

Only match I could find was a 70 351 non- ram air lid but would guess those are not reproduced

So the question would be - can the reproductions slightly longer be made to fit?

[mungus]

Thanks Jeff, appreciate the prompt response.

No wonder I couldn't tell, if the difference is only 1/4" over 17 odd inches of diameter.
The remnants I scooped out of the rim edge look like a hollow oval rubber that had been glued in many moons ago. Squashed almost flat, and cracked etc as one would expect from 48 years of age.

As far as I can see the replacements offered are just a length of suitably profiled rubber, so I can't imagine there is any problem cutting one down a bit. Anyway thanks for the information, sounds like I have a solution now.

[mungus]

Well the plot thickens...

I just measured a friends 67' 390 factory air cleaner and its OD is 16.75" vs mine at 17.75". So its a whole inch bigger. Which may explain why they don't fit the other gaskets. Strange thing is the C8ZZ-9673 replacement lid gasket from Scott-Drake covers the small blocks AND the 67' 390 only. So me thinks there is possibly a bigger change than 1/4". I'm googling to see if anyone has written about air cleaner sizes from early 68' cars on, when they dumped the spoked lid.

For what its worth a quick comparison with a post 68' Mercury 302-4V air cleaner at the local Mustang wreckers just now, showed that cars air cleaner (and lid) to be the same dimensions as mine. Like the other "post-spoked" V8 Mustang air cleaners I've seen, that cleaner body and lid looks the same as mine (except for the LHS vacuum operated round door of course). And likewise several post 68' air cleaners and lids are on eBay right now, all the listings that bothered with measurements saying 17-3/4". Although one oddly enough, says his re-chromed lid only fits non smog cars... (how on earth does that affect the lid?). Anyway know more on that angle?


 

[J_Speegle]

Unfortunately the MPC (looking at a April 68 one at the moment) show only the OD of the air cleaner assembly. Since the lid is the widest part one might assume that it would represent the lids diameter but can be sure.

It lists

68 - 390 for Mustang as being 17" in dia 

67 - 390 for a Mustang (and T-Bird) as being 16.79" in dia

68 - 289 & 302 for Mustang as being 17.84"  Same as  Fairlane/Torino with the X code, T-Bird with the S code and full size Ford with the 390 or 428 except for the police car

67 - 289 in a Mustang is shown as 17 1/4" in dia

Could you have a different air cleaner than the original?  Starting to look that way ffrom here based only on what you've provided and what the documents offer

[mungus]

I am guessing they must be lid dimensions as the 67' 390 lid I measured ties up with the figure you have.

Mine has the round vacuum door so perhaps it's from a T bird S code? Did they have that door like the Mustang S code? I would never have guessed that if you hadn't suggested it, as it looks "right", had patina, the round vacuum door and even the 390 sticker on the front. However perhaps that what it is.

My lid OD is 17.75" however the body is 17.0". But if it seeems the lid's OD is the definition then I guess that's not worth getting my hopes up over!  They fit together perfectly, and their paint and patina match, so I think they are likely an original pair.

UPDATE: I remeasured the lid, and is the 17.84" you mentioned.

So there are several sizes for the same year on Ford 390 V8's. Is it something to do with a Mustang's under bonnet shapes? Maybe a 17" lid is a better fit under there? But that only makes sense if the relative position of the carburettor differs from the 302 of the same year, seeming as they have the 17.84". The height of my air cleaner is the same as that quoted for the correct 390 GT one. So can't see that as an issue.

[J_Speegle]

So there are several sizes for the same year on Ford 390 V8's. Is it something to do with a Mustang's under bonnet shapes? ............

By 67  Yes. The size of the air cleaner is limited in the Mustang and Cougar when compare to larger bodied cars Ford built. It's not unusual (especially in a higher performance engine) for the air cleaner to be swapped out for a performance aftermarket air cleaner, then one a restoration begins for the owner to search and find a replacement. Unfortunately they don't always find one specific for their applications

[mungus]

I agree, that's the most likely scenario. I've just noticed that rather than spot welds around the vacuum door hole, someone has MIG'd it on. So I think what I must have is an elaborate fake, built using a 302/351 air cleaner.
Likewise the snorkel, which also looks correct, appears to have had its spot welds drilled out, the bend reversed and then MIG'd back together and then nicely dressed with a sanding disc etc. The whole thing looks convincing enough but the measurements don't lie. It's not 17"...

The bummer is I just missed buying a rare NOS correct 68' air cleaner on eBay a few hours ago. Not cheap at $750 (only got 1 bidder mind you), but then they never are, and it was NOS in its FoMoCo box, complete with a tested OK vacuum motor. Although the lid needed chroming.

One thing I have noticed is that the sellers of the replica 67' GT390 air cleaners are claiming these were also used on some early 68' 390GT cars. Is this true? Only that I have one of those on the shelf. Maybe not correct for my car with a March build, but perhaps a worthy substitute until a complete 68' cleaner comes along...

[J_Speegle]

One thing I have noticed is that the sellers of the replica 67' GT390 air cleaners are claiming these were also used on some early 68' 390GT cars. Is this true? ...

Guess your referring to the open style that is being reproduced that lacks the snorkel. No IMHO that was nor used in 68 production and would not have been approved for the 50 state wide emission standards that started in 68 for the S codes or other applications. Likely something some one found (again air cleaners got removed and replaced allot by POs) or two cars done that way and thought it was factory.  Way too many owners, especially in years past, that just put on what fit because "who's going to know the difference"