ADHA to DFEV carb/manifold swap on '79

[wetminkey]

dinghyguy! I've got a set of plugs for a single plane manifold for you! Once you've double checked your new manifold vacuum port sizes, I'll send 'em to ya. And rebuilding your DFEV should be a piece of cake,...!
Yeah, PaulC, we've been watching your thread,...thanks for the manifold plug sizes! I'll bet the ADFA is a pretty easy rebuild also. Rebuilding the ADHA is crazy. It has SO many diaphragms! I've never seen a carb with so much garbage added on for pollution control! Enough to make it PRONE to failure,...
Please let me know if there is anything I can do for either of you!
Todd.

[PaulC]

Yeah,only two useful ones - choke pull off and accelerator diaphragms.
Leaving off the high speed idle unit since none of the controlling elements are present anyway ( like a bunch of switches and electrovalves).
Then I'll just plug the vacuum port on the carb.

[wetminkey]

Oh, and lastly (for those that have got it),...
Automatic transmission kick-down should be adjusted with throttle arm disconnected. Just before the accelerator pedal comes to it's stop, the transmission kick-down cable should be pulled 7 - 9mm for the tranny to downshift.
I think that covers the whole swap (I'll add pics of my CCV to air cleaner modification when I get it done).
I hope others will advise further and add pictures too,...it would be really good to see variations on this. Again, I hope this thread will be easily searchable and will benefit other members.
Enjoy your Spider!
Todd Compton.

[wetminkey]

Well, I sure was hoping to do better on this part, but no.
The straight brass fitting that I was sent is not 1/2" thread, but threaded 1/2" NPT, so the thread is just a bit larger than 3/4". The hose barb is correct, at 3/4", though, so I rat-tail filed the 1/2" hole in the baseplate of my DFEV's new air cleaner to 3/4" and threaded the fitting into it. Worked perfectly, and provides a large diameter for crankcase ventilation, so it will not tend to plug at a restriction. The fitting will reside on the driver's side, front corner of the air cleaner baseplate.
Placed my stock flame-trap back in the carb end of the CCV pipe, slipped it onto the brass fitting, and attached the aircleaner baseplate to the DFEV. Nice strong clips to hold the air cleaner together,...
I'd add a pic, but I doubt it to be necessary,...
The new manifold, carb and air cleaner sure look great,...and the extra space under the hood!
Now I have to see if I can get my stock snorkel attached to my DFEV through an air cleaner,...after I get this car's front wheels aligned and finally get some driving time in! It's time,...it's spring!
All have a great day tomorrow!
Todd.

[wetminkey]

Happy Easter!
The 1979 Fiat Spider 2000/TH180 automatic transmission is an ENTIRELY different vehicle with a single plane manifold and a 32/36 DFEV Weber!
The Spider deserves this kind of performance,...
Obviously we've been out of the garage (even if for only a few short runs after warmup),...
Mas, manyana.

[geospider]

Congrats on finishing the job. It is quite a change. sounds like it all went well.
Enjoy the ride.

Geo

[wetminkey]

Thanks, geo! Just fine tuning now, after filling the Spider's belly with fresh fuel. But performing better than the car has ever performed. The drivetrain is holding up to the increased strain, so far,...brakes, too!
When I've got it really close, I'll 'get on it', and see what the Spider's new configuration can do.
I will enjoy the ride, thanks!

[wetminkey]

Done.
(the rest of the air cleaner clips go on after I'm positive of the choke adjustment)

Now, I'll see if I can get that big stock snorkel hose and the DFEV plumbed together, with an air cleaner in between. I'll be putting some engineering/planning into that in the future,...
Todd.

[dinghyguy]

Looks great todd.
A question for you...when you mounted the new single plane manifold to the 79 head did you find a passage and a threaded hole at the front of the heat that was not covered by the new manifold flange? I think the passage went to some bit of pollution control stuff that is no longer there at the front of the old intake manifold. Other than that the studs all line up and all the other bolts are there but...…
I am a bit puzzled at the moment, never mind that the heater pipe does not have the tee off for the water choke....

But hey your plugs helped if only i can use the manifold...…

slightly puzzled Dinghyguy

[dinghyguy]

moments after my previous post i realized i could go look at my other 79 car that already has a single plane intake. the holes are uncovered thus must not matter.
Problem solved, and i am sure someone will tell us all in detail why it does not matter
cheers

a bit dim Dinghyguy…….

[wetminkey]

That would be the Exhaust Gas Recirculation opening at the front of the head. If you check the exhaust side of the head, you will find a pipe that carries exhaust gases to the front of the head. They travel through the hole at the front of the head to the old intake manifold for emissions purposes (recirculation). The hole should be blocked off on the intake side to prevent an exhaust leak (or sealed off on the exhaust side).
Anyway, check the top of page two in this thread,...I fashioned a plate to cover the hole, held in place using the unused old intake manifold bolt hole, just below it. I used the same bolt to secure the new strut to hold the dipstick. Worked perfect for both purposes,...no leak, and a solid mount for the new dipstick strut.
Hope your swap goes smoothly!
Todd.

[wetminkey]

And I wondered if the rest of the car's driveline would withstand the increased horsepower,...As I expected, no.
I gotta terrible clunk in my pillowblock!!
Time to pull and rebuild my driveshaft. What fun.
The Spider is already up on ramps, ready for me to start the project,...

[y2kdeuce]

One too many neutral drops in front of the high school? #fixItAgainTony

[wetminkey]

No where near THAT much fun! Just one full throttle run from a stop,...
And automatic transmission,...!
Fix It Again Todd!
P.S. Wear on shaft makes it toast,...new, complete driveshaft will arrive on Thursday. Hopefully we will keep breakage down to a minimum after this,...

[volzke]

Wetminkey do you know off hand where to get a three port vacuum tee for a 1800 single plane manifold? Checked all of the usual places (AR, Vicks, MidwestBayless), and they only have two port tees. One for the brake booster and one extra vacuum line. Our '79 has an auto trans., so I need an extra vacuum line. Beings you had the same setup, curious where you sourced yours from. Getting pieces in place for a 1800 Single Plane and 34 ADF install on our '79. Was originally going to start on it this spring; but got bogged down with my A-Arms, Tie Rods, Wheel Bearings, Shocks, Brakes, and Tire install, ha! Suspension work should be good for awhile. I'm hoping to do a thread similar to this for the 34ADF. It'll be very similar, but a few small differences due to the carb layout and the water choke setup. Thanks!