28/32 ADHA to 32 ADFA

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gmichaud

28/32 ADHA to 32 ADFA

Post by gmichaud »

I'm in the process of removing the old 28/32 ADHA and dual-plane manifold to replace with a 32 ADFA (that I have rebuilt) and an 1800 manifold. So far so good. However after I repalce my starter (being rebuilt), I'll install the manifold and carb installation.

Before the 32 ADFA goes into the car, I have to do something with the carburetor accelerator linkage. The 32 has a cable pull setup, while the 28/32 setup was a ball and socket setup with linkage assembly on the cam box cover. Can the 32's linkage simply be taken off and simply replaced with the linkage piece presently on the 28/32? The switch can clearly be done, but there are differences, one of which is the springs may not allow proper actuation of the ball and socket lever onece on hte 32 ADFA. Has anyone ever had to do this? Anything to adapt? I've added pictures for clarification. Thanks to anyone who can help.

Gil

28/32 setup - https://dl.dropboxusercontent.com/u/398 ... socket.jpg
32 ADFA etup - https://dl.dropboxusercontent.com/u/398 ... inkage.JPG
Warren
Posts: 132
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Your car is a: 1979 Fiat Spider

Re: 28/32 ADHA to 32 ADFA

Post by Warren »

I now use a 34ADF on my 1979 but previously used a 32ADFA and still have that carb. I went and looked at it and either I transfered the ball socket lever to it from the 28/32ADHA or it came with it already; just cannot remember as that was several years ago. I can supply a picture if you email me at whhopson@southernco.com.
Warren
Sylacauga Alabama
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1991 Alfa Romeo Spider Veloce
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gmichaud

Re: 28/32 ADHA to 32 ADFA

Post by gmichaud »

Thanks Warren. I suspect there may have been different linkage levers types on the 32 ADFA. I've gotten a hold of a 32 ADFA that has the ball and scoket lever I need. I'll take off the mechanism on my rebuilt 32 and repalce with the proper lever.

Gil
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MrJD
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Re: 28/32 ADHA to 32 ADFA

Post by MrJD »

Going to bump this up as I will be doing it soon.

Later ADFA carbs had lots of emissions restrictions going on. I will soon be swapping doing the single plane and 32adfa swap on my 79 carb spider. I will re-build the adfa before installing. Should I do anything extra to it to make it more performance oriented for a 2.0 engine? I am thinking in terms of jets, or anything else for that matter.

I want as clean of an installation as is possible.
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toplessexpat
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Location: Houston, TX

Re: 28/32 ADHA to 32 ADFA

Post by toplessexpat »

Why not put a 34ADF in instead?

Brad has a great discussion on such matters in here.. http://www.artigue.com/fiatcontent/Arti ... 124_MM.pdf Page 87/88 has the "suggested" carb/manifold pairings for different blocks. I've found the entire document really very interesting and useful.

There's also a great little guide he did on the ADF/ADFA which I found here http://www.njfiats.org/joomla/images/st ... er_adf.pdf

Hope these help

Andy
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BEEK
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Re: 28/32 ADHA to 32 ADFA

Post by BEEK »

toplessexpat, yours has a 34adf :)
Automotive Service Technology Instructor (34 year Fiat mechanic)
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toplessexpat
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Re: 28/32 ADHA to 32 ADFA

Post by toplessexpat »

Not any more :)
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MrJD
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Re: 28/32 ADHA to 32 ADFA

Post by MrJD »

the 34adf would cost me about 7x more money, and would not make for 7x more performance.

I want the car on the road sooner rather than later. In a few years, I might do a full performance rebuild and buy some dual IDF's. For now, I just don't want to deal with the crap stock carb.

So, being that I will rebuild it, I'd like to set it up as well as I can. So, if i can change internals to get a bit more power, that would be great.
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toplessexpat
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Re: 28/32 ADHA to 32 ADFA

Post by toplessexpat »

MrJD wrote:the 34adf would cost me about 7x more money, and would not make for 7x more performance..
... and that's a REALLY good reason for not doing it.

I'd send Brad (Artigue) a note, he seems to have much of the resident brain trust on carbs... but I'm sure others have some opinions too!

A
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narfire
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Re: 28/32 ADHA to 32 ADFA

Post by narfire »

A fellow here found a 34 DMSA and installed it with single plane on his 79. He said it was like a different car, way more power compared to stock. Evidently a complete rebuild kit is hard to find though.
Yes the 34 ADF is expensive...around $500.00 new. The 34 DMSA not so much if you can find one.
Chris
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toplessexpat
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Re: 28/32 ADHA to 32 ADFA

Post by toplessexpat »

Just did a quick flea-bay search..

http://www.ebay.com/itm/WEBER-34-ADF-Ca ... 4897.l4276

$295 seems fairly keenly priced...

A
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MrJD
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Re: 28/32 ADHA to 32 ADFA

Post by MrJD »

Not when you consider that I will have less than half of that in a adfa AND single plane manifold rebuilt and on the car.

I'll send Artigue a message.
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bradartigue
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Re: 28/32 ADHA to 32 ADFA

Post by bradartigue »

I don't think that ADFA came from a FIAT, and that's fine, that big spring loaded thing from the cable assembly can be removed and the ADHA one should install with little effort. They are the same carburetor in most respects, and the primary linkage should be damn near identical. I think I had to slightly file the ADHA one to fit the ADF at some point in time, but whatever I've done never took more than an hour of labor from start to finish.

The biggest single improvement you'll find is the secondary opens when you press the gas, which is something the ADHA didn't do. So if you want to go fast quickly you can, because you can dump 2.5x more fuel and air into the engine on demand.

You'll likely love it for the first few minutes and then say "Hey there is a mild flat spot during acceleration." If so increase both main jets to the next size up, it should go away. Otherwise just tune it as any carburetor and haul ass.
131
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Re: 28/32 ADHA to 32 ADFA

Post by 131 »

bradartigue wrote:I don't think that ADFA came from a FIAT
Don't think they were ever on a 124, but they were standard on OZ 2 litre 131s.
Mick.

'82 2litre 131, rally cams, IDFs & headers.
pwilliam
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Re: 28/32 ADHA to 32 ADFA

Post by pwilliam »

Is there much benefit to putting a different carb on the 79 dual plane manifold? Have to deal with CA smog and want to just be able to swap carbs quickly before taking it in while still getting an improvement in performance.
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