Topic: Which vacuum unit is correct for my March 68' S code?

[mungus]

Hi All,

Noob here so please excuse my ignorance. I have a Metuchen built, mid March assembled, 1968 S code fastback. Which I am in the process of rebuilding.

It came missing its distributor, so I am hunting one down, however I've noted looking at web photos and some blurb on other forums, that some 68' FE390 distributors had a single advance and some had the big double vacuum advance. I've read that they started with a single then got changed at some point during the 68 model run, to help emissions.

Have had a look at the Mustang Tek website of course, and that offers 4 possible Autolite dizzys, with only one as confirmed (C8OF-12127-D a'la 428CJ), the other 3 TBC;
(C7AF-12127-AC, C7AF-12127-L & C7OF-12127-F).

So does anyone know definitively what type I should have?  (both distributor & vacuum unit)
I'm not a fanatic, but where possible I'd like my engine bay looking right. And that distributor is right in your face! 

Thanks in advance. (pun intended!) 

[Bob Gaines]

Hi All,

Noob here so please excuse my ignorance. I have a Metuchen built, mid March assembled, 1968 S code fastback. Which I am in the process of rebuilding.

It came missing its distributor, so I am hunting one down, however I've noted looking at web photos and some blurb on other forums, that some 68' FE390 distributors had a single advance and some had the big double vacuum advance. I've read that they started with a single then got changed at some point during the 68 model run, to help emissions.

Have had a look at the Mustang Tek website of course, and that offers 4 possible Autolite dizzys, with only one as confirmed (C8OF-12127-D a'la 428CJ), the other 3 TBC;
(C7AF-12127-AC, C7AF-12127-L & C7OF-12127-F).

So does anyone know definitively what type I should have?  (both distributor & vacuum unit)
I'm not a fanatic, but where possible I'd like my engine bay looking right. And that distributor is right in your face! 

Thanks in advance. (pun intended!) 

Also need to know if auto or 4 speed.

[mungus]

Was a C6 auto. However, sacrilegious as it may be to some, I'm fitting a Modern Driveline TKO600 kit to mine. 
Mine is not going to be strictly concourse, as I'm aiming to make a faithful Bullitt replica.
But besides that issue, I intend for it to be a factory Highland Green 68' S code manual FB, (save the Torque Thrust wheels and Bullitt trim deletions).
At least in appearance (engine may well be moderately upgraded internally; e.g. mild HYD roller cam & Petronix etc).
 
Sorry about that Bob, I know there are differences in smog systems etc, for the 4 speed vs. auto. My bad!

[WT8095]

All '68 S codes sold in the U.S. had Thermactor emissions and used the C8OF-D distributor. The dual diaphragm vacuum unit was included under the distributor part number.

Update: removed erroneous reference.

[mungus]

Many thanks, that's great information.

[mungus]

So just to educate me, if all 68' S codes had the thermactor system, why are the smog heads sometimes called California heads? Did CA just get lumbered with the thermactor system first, or was it only west coast cars that had that in that time?

Excuse my ignorance, just trying to learn. If someone can direct me to a source of such detailed info I can stop annoying people here! 

 I see my S code has the little smog ports on the heads. Even though it's a Metuchen car. If that's correct fir the car,  (casting codes are OK, but who knows where the heads really came from), may I ask what people in the know have done to work with or around that system? Do they just plug the holes up? Plug the tube ends to keep stock appearance but restore some performance? Or is it possible to build a decent engine and still use that thermactor system as intended?

I'm sure there's no substitute for experience in such matters, so would appreciate others views.

[70cj428]

All '68 S codes sold in the U.S. had Thermactor emissions and used the C8OF-D distributor for A/T and C8OF-C for M/T

Are you sure about this?

My 68 S code Metuchen 4 speed car (July 68 build) has a C8OF-D Dual diaphragm distributor that I'm sure is original, ( I think this is also confirmed in the MPC)

And if I'm not mistaken, a C8OF-12127-C distributor is a small block distributor


I Think the term "California" head refers to earlier small block heads where the Thermactor pump was only a California thing. By 1968 all "S" code Mustangs sold in the US had a Thermactor system. ( The same is true with 428CJ's, all US sold 428 CJ's were equipped with a Thermactor pump.)

Ford sold special plugs to plug those holes if you don't want to use the system, just plug the holes and leave the system off. If you have AC, you'll need to run a shorter belt after removing the pump.

Hope this helps, John

[krelboyne]

1966-67 California had Thermactor smog on most Ford cars and light duty trucks. However, this is a completely different set of smog components that found starting in 1968.

In 1968, Ford cars and light duty trucks with manual transmissions (including 6 cylinder engines) should have been delivered with a Thermactor smog system for all 50 United States. Additionally, if your engine came equipped with a Holley carburetor (automatic or any manual transmission) it also received a Thermactor smog system.
*Note - 1968 Ford cars delivered to Canada would have an 'open' emissions system. Marti Report designated "Non-Emissions System".

[mungus]

Are you sure about this?
My 68 S code Metuchen 4 speed car (July 68 build) has a C8OF-D Dual diaphragm distributor that I'm sure is original, ( I think this is also confirmed in the MPC)
And if I'm not mistaken, a C8OF-12127-C distributor is a small block distributor
I Think the term "California" head refers to earlier small block heads where the Thermactor pump was only a California thing. By 1968 all "S" code Mustangs sold in the US had a Thermactor system.
Hope this helps, John

Thanks John, it does indeed help, especially coming from someone with the exact same car / year / factory.

I can see how the moniker of California head may have applied erroneously to later cars.

My heads have a set of matching hex headed plugs fitted. Looks factory and have identical thread depths etc, so I'm guessing they are the FORD plugs. Happy to leave it that way, as I find the smog system butt ugly and needless complication. Although I may well restore and box up the pump and pipes just to keep the cars bits together.

[WT8095]

Are you sure about this?

My 68 S code Metuchen 4 speed car (July 68 build) has a C8OF-D Dual diaphragm distributor that I'm sure is original, ( I think this is also confirmed in the MPC)

And if I'm not mistaken, a C8OF-12127-C distributor is a small block distributor


I Think the term "California" head refers to earlier small block heads where the Thermactor pump was only a California thing. By 1968 all "S" code Mustangs sold in the US had a Thermactor system. ( The same is true with 428CJ's, all US sold 428 CJ's were equipped with a Thermactor pump.)

Ford sold special plugs to plug those holes if you don't want to use the system, just plug the holes and leave the system off. If you have AC, you'll need to run a shorter belt after removing the pump.

Hope this helps, John

Yes, the C8OF-D distributor was for both A/T and M/T. I mixed it up with the carburetor IDs. I'll correct my post.

[J_Speegle]

Ford sold special plugs to plug those holes if you don't want to use the system, just plug the holes and leave the system off. If you have AC, you'll need to run a shorter belt after removing the pump.

Believe the plugs were made so that thermactor heads (rebuilt or otherwise) could be used on Non-thermactor equipped engines. Doing the opposite (removing a system) would have been illegal in some states or federally depending on when the car was built.

Even today where annual tests are not conducted many states still have the rule (and can enforce it) on the books. Know California is still that way.

[70cj428]

Even today where annual tests are not conducted many states still have the rule (and can enforce it) on the books. Know California is still that way.

I'm pretty sure PA is still that way, they got rid of pre 1975 emission testing, but I'm pretty sure you still have to pass a visual inspection. The good thing is that even if the inspection mechanic actually looked, most would have no clue what was supposed to be there....

[Scott Fuller]

Know California is still that way.

Jeff,  You know that they don't inspect 68 in CA.  And if they are from out of state it's only for the VIN.

Scott

[jwc66k]

You know that they don't inspect 68 in CA.  And if they are from out of state it's only for the VIN.

It's also against the law to alter or remove emission control equipment on all vehicles (includes PCV valves on 65 and earlier). However, enforcement is virtually non-existent. To be truthful, very few enforcement or repair personnel have an idea what any early equipment looks like or how to test it. The only time such equipment is inspected is at certain car shows, and then only for appearance.
Jim
 

[J_Speegle]

Jeff,  You know that they don't inspect 68 in CA.  And if they are from out of state it's only for the VIN.

Yes I know but you still, by law, have to have the equipment on the car and if one of the road side sniffers catches you with high concentrations and sends you a naughty note to go to an inspector station it's a mess. Then they look 

One big challenge is that BAR doesn't have the documentation (well correct info) on the Ford products like they do on others. Been years since they called me to help settle some things but at that time allot did not match up with what was done

Back when I spoke to the state assembly subcommittee, when they dropped the annual inspections, that is what was spelled out and put in the law. Every year or two they bring up the inspections again though so far they have not gotten it back. Not sure if the current (think its bill 350)  its included in there with the fuel rationing and other fines so are trying to get passed.


Think we've gotten well off thread