.Re: Aircraft Carb on Packard Engine ?

I just found a good Aircraft type Carburator, (Stromberg S3A1, updraft), that I think was removed from an A-65 Continental engine, that I forgot I had. It is a very simple and reliable carb. designed for a gravity feed system. So I was thinking about adapting it to be used on the '29 Super-8, If the Standard-8 carb I'm using now doesn't give the 'Neck Snappin Power' that I want. <img src="http://forums.aaca.org/images/graemlins/cool.gif" alt="" />

Should be easy to adapted it to manifold.

And it's very easy to attach an air-filter to these carbs, unlike the originals.

Has anyone ever heard of that being done before?

Here's a pic of S3A1 Carb:

See Attachment:

Not as easy as it first appears.

You need to know if the cubic inch displacement of the aircraft engine is approximately the same as your Packard. Otherwise, you could be way rich or way lean unless you rejet it.

Does the aircraft carb have an accelerator pump? If not, you're likely to bog down on acceleration.

As for altitude considerations, I have no clue. Don't aircraft have a huge mixture adjustment capability to help cope? Don't know, as I'm not a pilot.

The carb has adjustable jeting and since the inside ventura diameter is close to or a little larger than the manifold inlet, and the mixture control could be set to a fixed adjustment and not need an adjustment control (like needed with altitude changes), so I don't think there would be a problem with those, but it's the acceleration and deceleration that I'm not sure about. In aircraft you usually don't make as many rapid changes in engine speed like in a car, altho I have done rapid changes in speed when doing airobatic manuvers, so I think it would be okay there also. I think it has an accelerator pump, but I'll need to verify that.

It's a '31 Packard with an updraft carburetor--the soft spoken boss of the road, the American Rolls Royce, etc.--it's never going to have "neck snappin' power". Bill Ruger has a Stutz DV-32, a car he's very fond of. It was restored by a very good restorer to be as good, if not better than when new. It was not easy to start, not great on performance. He took it down the road to his neighbors at Callaway (the Corvette-rodding company) and said "what can you do that won't affect the originality, any changes have to be bolt-on, bolt-off, but make it run better." They engineered a 6V electronic fuel injection system with a custom made intake plenum, sensors on bolt-on brackets, everything added so as to not affect the originality. Bill can take all of it off and bolt his old intake and carb on and have the "original George" again. The car starts RIGHT away, has a smooth idle and terrific performance, much better than with the OE updraft carb.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body"> They engineered a 6V electronic fuel injection system with a custom made intake plenum, sensors on bolt-on brackets, everything added so as to not affect the originality. </div></div>

I would Sure like to see that. <img src="http://forums.aaca.org/images/graemlins/smile.gif" alt="" />

{Neck-Snappin' Rules!) <img src="http://forums.aaca.org/images/graemlins/shocked.gif" alt="" /> <img src="http://forums.aaca.org/images/graemlins/grin.gif" alt="" />

Well, it appears that the S3A1 Carb does Not have an accelerator-pump, so it would not be a good one to use. Too bad, cause other than that, It would be Great. Maybe there's another similar carb that does have pump, that I could trade for, I'll check on that.

You often see Ball and Ball (B& carbs fitted to early updraft engines.

Is there a B&B Carb Model that will fit a Super-8 manifold, which is larger than Standard-8, or will an adapter be needed to connect them.

I can't answer that. Maybe talk to the carb guru who posts now and then? CarbDoctor?

The largest Carter BB series carb is an S.A.E. size 3. The Packard Super 8 used an S.A.E. size 4 carb. Size 4 carbs which we have used on Super 8 Packards are:

Stromberg SF-4, and SFM-4

Zenith 63AW14 and 263M2E14

Since Packard used a cross flange carb (a line through the center of the mounting bolts would run fender to fender) and these carburetors are straight flange, a 90 degree adapter is necessary.

It is also necessary to redo the linkage to convert the "MM" Packard rotating linkage to conventional push-pull.

Of course, you could always purchase one of the repro Speedster 2 barrel manifolds, and install a 2 barrel carb. <img src="http://forums.aaca.org/images/graemlins/smirk.gif" alt="" />

Jon.

Thanks for the Info, Jon

Can you explain what Size 3 and 4 mean?

Is that just a reference part number or does it somehow relate to the Venturi size, or Something else?

Rick - The Society of Automotive Engineers set "standards" for many items, including carburetor size. The flange size refers to the physical size of the mounting flange.

Size 3 has center to center stud spacing of 2 15/16 inches, and is referred to as a "nominal" 1 1/2 inch carburetor, although the throttle bore will range from about 1 5/8 (very efficient carbs) to 1 15/16 (very inefficient carbs).

Size 4 has center to center stud spacing of 3 5/16 inches, and is referred to as a "nominal" 1 3/4 inch carburetor, with throttle bore size ranging from about 1 7/8 to 2 1/8.

Within each flange size, there may be from 3 to 9 internal venturi sizes, and of course the venturi is the primary consideration in determination of air flow.

The original Detroit Lubricator was an excellent carburetor in its day, and still is, if one is not blessed with ethanol fuel. As the Detroit is an "automatic" carburetor, adjustment for different fuel energy content is not easy. The aspirator spring needs to be wound to a different tension. If one is not blessed with ethanol; one can still make the Detroit work well provided one compensates for the wear in the groove of the aspirator valve, and the "fingers" of the vanes. One also needs to make sure the vane box is true and not warped.

Jon.

Okay, Great Information.

Thanks,

Rick:

Any interest in getting rid of that carb? I think I am gonna need one for my Cub soon.

No, Sorry, I think I'll hang on to it for Now.

It does really bring back memories of the 'Good Ol' Days'. <img src="http://forums.aaca.org/images/graemlins/smile.gif" alt="" />

.

A little additional information to this thread.

It would seem that Rick is wishing to replace the Detroit Lubricator on a Packard Super. As mentioned previously, the Packard Super uses an S.A.E. size 4 carburetor. Size 4 carburetors which may be made to work extremely well on the Packard Super are the Stromberg SF-4 (SFM-4 marine) and Zenith 63AW14 (263M214 marine).

The original Detroit, when properly restored by someone who understands the carburetor, will work extremely well in all functions except starting, where it has (opinion) an inferior starting mechanism.

It is well-known that increased richness is required to start and maintain a cold engine. There are two methods commonly in use. Most U.S. manufacturers chose the method with a choke plate (constant fuel, reduced air); however Detroit chose to use the method preferred in Europe (constant air, increased fuel). (Opinion) the method of constant fuel, reduced air works much better for an updraft carb.

Once the engine has started and warmed, the Detroit should idle smoothly and provide excellent driveability, acceleration, and WOT power.

Another poster mentioned EFI. I won't debate the merits here, but updraft carbs with choke butterflies can start an engine extremely well. I have personally had several engines with updraft or sidedraft carbs that were crank started and would start on 1/2 revolution of the engine! Often, the updraft carburetor receives the blame that should be directed at an inefficient electrical system. Many restorers tend to paint everything, thus effecting a poor ground contact, and killing the voltage to the coil. I have personally demonstrated to many this effect simply by taking a jumper cable from the ground terminal on the battery to an engine head bolt, and watching their engine start on the first revolution.

When restoring the Detroit, some issues to that MUST be addressed for proper performance are the vane box and the aspirator valve and vanes. The original zinc alloy vane box warps! This box, or vane support, must allow the vanes to move freely, yet minimize the air loss between the edges of the vanes and the side of the support. Generally, the best route is to replace the original vane box. The aspirator valve, in theory, was supposed to rotate on the vertical standpipe. In practice, rotation did not occur, and the valve simply moves in a vertical plane only. This causes wear in the upper side of the groove in the aspirator valve and also on the fingers of the vanes. When restoring a Detroit, it is imperative that this wear is reversed. This may be done by metal spray on the "flats" in the groove of the valve, then turning in a lathe, and building up the fingers on the vanes; or if one does not have these tools readily available, the aspirator valve and vanes should be replaced.

Since the Detroit is an "automatic" carburetor, the wear changes the geometry of the fuel curve and one acquires the infamous Detroit "it will run well but won't idle, or if I adjust it, it will idle well but won't run".

Jon.