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Discussion Starter #1
Hello All -
After going back and forth (for a long time now) about the Spica vs. Weber question, I have finally chosen to go with the dual Weber 40DCOE setup. I believe I have all the parts necessary to make the conversion, I am just looking for advice / commentary / knowledge from someone who has done it before.
What should I look out for? What potential gremlins are lurking in there? Any parts (pics to follow shortly) I don't have but need? Tips for making the process go more smoothly?
Any and all comments are welcome.
Thanks in advance,
Peter
 

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I believe I have all the parts necessary to make the conversion, I am just looking for advice / commentary / knowledge from someone who has done it before. What should I look out for? What potential gremlins are lurking in there?
Well, since you haven't given us a list of which parts you already have, it's pretty hard to advise you on what you're missing!

Got the shorter studs needed to mount the factory Weber intake manifold? Got a carb-air box support rod that's the right length for your 1750 or 2L engine? Got the correct coolant hoses to fit your ??? style intake manifold? Got a throttle pedal & linkage assembly from a carbureted car?
 

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Discussion Starter #3
Jay -
Thanks for the quick response.
Shorter studs? Check
Box support rod? Check
Pedal and Linkage? Check

 

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Discussion Starter #7
while we're at it...how do I post a pic directly into the post / reply?
 

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Time to get to work Peter. Along the way you will discover some minor glitches, but this is a straight forward project. Do your Webers match? Have you consulted and/ or checked chokes and jetting?
 

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Discussion Starter #10
Gordon -
I believe the Webers match.
Chokes and jetting appear to be correct, but then again, I guess we'll see once installed.
Peter
 

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OK, the picture is worth a thousand ..... well, you know

Parts not shown in your picture:

- Looks like you need the rubber isolators that go between the manifold and carbs.
- The manifold doesn't have the bung for the power brake vacuum - you should be able to steal the one off your Spica manifold.
- You seem to need a thermostat and I think upper thermostat housing - again, the ones from your Spica manifold should fit.
- Strap clamps to hold the upper air filter housing to the air box. The circular, back cap for the filter, and wing nut to hold it on. Oh, and a filter cartridge.
- I always connect the choke cable to my Webers - other people say it's unnecessary, but since Weber provides the enrichment lever, I feel it ought to be hooked up. I use a wire instead of a braided cable, as a cable will fray where the pinch bolt compresses it. And, tighten the pinch bolts before seating the carbs against the soft mounts - once the carbs are in place, the bolts get obstructed by the manifold.
- Various nuts & bolts, hoses, hose clamps, etc.
 

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Discussion Starter #12
Jay -
You are very observant!
I have the cap for the air box, and the straps as well.
Filter cartridge is on its way...
Thermostat, brake vacuum bung, upper thermostat housing...not pictured.
And yes, I plan on connecting a choke cable to the Webers.
Rubber isolators that go between the manifold and carbs?
Are those the $.95 gaskets Centerline sells or are you referring to something else?
Thanks for the informed comments...
Peter
 

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Rubber isolators that go between the manifold and carbs? Are those the $.95 gaskets Centerline sells or are you referring to something else?
No, you need another $100 worth of parts - see Centerline p/n WC106 and WC110 (pictured below). Use two WC106's for cylinders #1 and 4, and use one WC110 for #2 and 3. You will also need eight of those $.95 gaskets to go on either side of these rubber isolators. And a ground strap between one of the carbs and the manifold to dissipate static electricity (Centerline WC400 - picture at bottom).

If you hold your carbs up to the manifold, you will see that the 8 mounting holes don't align at all. You need these rubber isolators to get the studs to line up, to position the carbs out where they will pick up the airbox, and to keep fuel in the bowls from foaming due to vibration.



 

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Discussion Starter #14
Jay -
Ah, those...
Yes, those are on their way Centerline as well.
Thanks!
Peter
 

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You are also missing a fuel pressure regulator. Webers need pressure limited to 3.5 to 4 psi. Drop the fuel tank pump (waaaay to high pressure) and use an external solid state or bendix pump. Traditionally mounted under the car behind the rear axle (near the pump). Be sure to check the float level in the carbs, and use a new needle valve (always in the overhaul kits).

The Alfa OEM pressure regulator has a glass sediment bowel as well.

If you fill the carbs with lacquer thinner (even better than carb cleaner and cheaper) and let it soak, then operate the throttle valves, you'll spray fluid out the accelerator pumps. There is a ball check valve in the bottom of the carbs that often gets gummed up. Just unscrew the cap and pour it in the un-attached carbs.

Robert
 

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Discussion Starter #16
Man...you guys are good! Yes, I have the Bendix style pump, it was just not pictured. Great advice about lacquer thinner and cleaning out the carbs in advance. Thanks, Robert.
So far I have received lots of equipment comments, but none regarding the installation process itself. Anyone care to chime in on that?
Peter
 

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So far I have received lots of equipment comments, but none regarding the installation process itself. Anyone care to chime in on that?
Whaddya mean "none regarding the installation process" ? I divulged my super secret choke wire attachent procedure in my post from Jan 21st at 1:45pm ! ;)

But seriously, other than the choke cable, it's pretty much "unbolt the dreaded Spica stuff", "bolt on the nice Weber stuff". A few other thoughts:

- Unbolting the Spica pump from the front cover is fun (not!). The four mounting studs are tough to access. The good news is that this will be the final grief your Spica system will cause you.

- I've never removed a throttle pedal assembly with the engine was still in the car - dunno how difficult it is to snake out the old part around the cylinder head.

- It looks like your horizontal rod that goes from the pedal assembly to the bellcrank is made of steel. Make SURE it cannot come in contact with the big "+" connection to the starter. Slipping a piece of tubing over that rod is cheap insurance against shorts.

- I know I keep advising you to get more parts from Centerline (I should be on commission!), but here's another tip: It appears that your two linkage rods have the Spica-style, plastic ends. The metal ends are a bit more reliable and look more vintage. These go for $7 apiece - cheap insurance, especially on the horizontal rod, since if it pops off, it's tougher to access and it could drop on that starter "+" terminal.

 

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- I've never removed a throttle pedal assembly with the engine was still in the car - dunno how difficult it is to snake out the old part around the cylinder head.
It's a pain but not impossible. Much easier with the engine out.

The horizontal link rod can also foul the support bracket for the air filter plenum. I had to grind away a bit of the bracket on two of my cars.
 

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Jay is right on the money about the long horizontal linkage rod. Having done a number of abnormale Giulietta and Giulia conversions over the years, should that rod touch the starter solenoid + terminal, you end up with arc welding going on inches away from fuel filled Webers, sometimes at SPEED! This always makes for interesting entertainment. In theory, but not in fact, the plastic rod ends should help avoid this problem. Do not mess with them with Webers. Also, it is a good idea to have that rod operate in as close to a horizontal plane as possible. It should not be pushing the rod down as it will bow and touch something it should not. This was always a problem with annormale conversions in the earlier cars, as the old Veloce Giulia / Giulietta system used a short hanger from the manifold combined with a different bell-crank than the later cars. This caused the long hanger / long rod to push down, bow, and touch things it should not. Your hanger may or may not need some alterations to keep the long rod pushing straight back (along with STEEL ends!).
 

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Manifold to head, carb and air cleaner gaskets?
And check and record the choke (venturi) size before mounting carbs.
Vic
NYAROC
 
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