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1967 Eldorado Air Injection Manifold removal?

Started by 67_Eldo, January 29, 2017, 06:51:16 PM

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67_Eldo

I have a '67 Eldo that has led an unloved life. It has accumulated only 66k miles, but it seems to have been shortchanged at every turn as far as maintenance goes.

It was a car built for the California market, so it sported an "Air Injection" setup when the first happy owner took delivery.

Somewhere along the line, somebody decided to remove the Air Injection system. The air pump is gone. However, they must have become frustrated while trying to remove the air-injection manifolds. The manifold on the passenger side bank is almost gone: The "mechanic" couldn't pull the manifold legs from the cylinder head, so he hacked off the connecting manifold pipe and crimped the legs closed. There are four little "tubes to nowhere" sticking out of the passenger-side cylinder head.

The drivers-side air-injection manifold remains in place. But since the pump and its plumbing is long gone, the left air-delivery hose runs down to where the air pump once was. At that point, the hose is plugged shut.

I wish I had photos to attach, but I'm not close to the car right now.

When you listen to it run, you hear a little puffing as if there is an exhaust-manifold leak. But after looking over this air-injection mess, I'll bet the puffing is coming from an air-injection remnant.

Here are my questions.

1. Can those air-manifold legs be removed from the cylinder heads? They are apparently press-fit connections and, after 50 years of use, seem to be essentially welded to the cylinder heads. If they can be removed, can the air-injection holes simply be plugged? Plugged with what?

2. Instead of messing with plugging the air-injection holes, should I replace the original California heads with non-California heads (with hardened seats and all the latest tweaks)? If so, who is a good source for replacement heads?

Thanks!

TJ Hopland

Late 60's a lot of cars started getting the air pumps so maybe all 67's had em?    I know the 67 head was a one year only thing mostly due to it using what became the 472's rocker design.    Hopefully someone that knows 67's better than I can tell you for sure.   If there were non smog manifolds they still may not be easy to find since you are dealing with a one year one model only combo there. 
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

67_Eldo

So the heads on a 67 are one-year-only heads?

As far as I can tell, the GM air-injection experiment only applied to larger GM cars from 66 to 67 that were sold in California. Later, when the nationwide air-polution mandate kicked in, GM used different systems.

I was starting to worry about that when I saw that the pushrods are unique to 67. But I was hoping that the oil passageways and rocker mounts hadn't changed from 65/66.

Thanks!

TJ Hopland

Story goes that the 472 was supposed to come out in 67 at least in the Eldorado but they had not yet completed the 'million mile' testing so the 429 had one more year.  Not sure why but it ended up with the 472's rockers and Quadrajet carb which required a new intake.

I'm not a 67 expert but since someone that really knows them has not responded yet I will keep guessing.   

I think the intake interchanges between 67 and earlier.  I would also assume the exhaust manifolds do too but since 67 was the first year for a FWD Eldo there would not be a 66 version.  Later Eldos the right manifold is the same as the RWD cars, not sure if this was true in 67 or not. 

The 472 rockers are on a T pedestal with a 'tin' retainer.   I believe most of the 429's were a more typical shaft system.  I don't know if most of the 429's were shaft oiled or pushrod.  The 472 version is pushrod.   

The 472 heads had an internal 'smog' passage so there was just a crossover tube between the heads at the front that the pump connected to.  As far a I know Cadillac was the only one to do that, everyone else had the external tubes in the manifolds.  Maybe no one else had space in the heads?   Most of the 472-500-425-368 cars had the smog pumps.  There were years or models here and there that didn't but most did. 
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

67_Eldo

Looking through the Modified Cadillac site (which I will join), I see this post that shows matching numbers for 64-67 non-AIR heads and matching numbers for 66-67 AIR heads.

http://www.modifiedcadillac.org/forum/index.php/topic,6018.0.html

At the moment, I hope I can remain an AIR head. However if I run into trouble, I'll be investigating the non-AIR world.

I did not know that the 472 was initially slated for the Eldorado. I thought Cadillac was working on a V12 that was cancelled late in the development process, so Cadillac had to go with a FWD-ized 429.

The '67 Eldorado certainly has its share of one-year-only bits and pieces!

Thanks again for the information!

Thanks!

TJ Hopland

Interesting that the same numbers are showing for 66-67.    I assumed they were different but maybe not?   I know you can get a shaft rocker system that bolts onto the 472-500 heads so maybe they just did the opposite and built a pedestal system to bolt onto the same locations as the shaft system.  Have you figured out if they were shaft or pushrod oiled? 

I don't know that the 472 project had anything to do specifically with the FWD Eldo, I think it was just an evolution in engines and it happened to time out with the FWD introduction. 

Another change for the 472 was to go to the 'standard' GM bell housing which Oldsmobile already had so the Tornado's transmission would be a direct bolt up.  The 67 Eldo more or less used adapters to make the 429 work with the BOP (Buick-Olds-Ponitac) transmission.   Seems like I read that it was not the exact same transmission.  Casting was the same but it was finished slightly different for the 67 with the 429.   Something like a slightly different pin location or some extra or missing holes. 

Ya first year cars are often the best looking but often had a lot of one year only things on them, usually for good reason, they had bugs.     
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

35-709

"I think the intake interchanges between 67 and earlier."

If you do put a '67 intake manifold on an earlier 429 you'll have to use the Q'Jet also.
Reverse is also true, earlier 429 intake on a '67 will require a Carter AFB (or Edlebrock) or Rochester.  Earlier carb with matching earlier air cleaner on a '67 Eldo may well cause hood interference problems.
1935 Cadillac Sedan resto-mod "Big Red"
1973 Cadillac Caribou - Sold - but still in the family
1950 Jaguar Mark V Saloon resto-mod - Sold
1942 Cadillac 6269 - Sold
1968 Pontiac Bonneville Convertible - Sold
1950 Packard 2dr. Club Sedan
1935 Glenn Pray - Auburn Boattail Speedster, Gen. 2

67_Eldo

The 67 is pushrod oiled.

It is impossible to realistically tell from photos, but the 66 & 67 heads sure look alike at a distance. I'm guessing that the 67 rocker assemblies would bolt up to 66 heads.

I'm keeping the intake and Q'Jet that I've got because they seem to be working well. Given the removal of the air-injection hardware and the plugging of various vacuum leaks, we'll see what happens once the carb is adjusted.

Since the original Q'Jet kickdown/switch-pitch switch died, I'm going to use an aftermarket switch for kickdown and Bruce Coe's switch-pitch controller for the (freshly rebuilt) TH435.

As I mentioned earlier, I hope I can stick with the heads I've got. But on a 50-year-old car, best-case scenarios don't always present themselves (as I've already learned with the transmission).

Thanks!