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Discussion Starter · #1 · (Edited)
I have a 71 Spider 1750 that has been converted to Webers, using one of the conversion kits. It uses the SPICA intake manifold and throttle linkage and K&N filters.
Weber Spica Conversion.jpg

It stumbles off idle, and the K&N's are just **** noisy. (does that mean I'm getting old? :confused:)

I -think- I have collected all of the parts necessary for the conversion to a true Euro carb intake manifold and air box. For the record, I got most of them from Guru in Romania.... full vote of confidence for here.
Anyhow:

Below is a pic of what I've gathered.... what am I missing?

Euro Throttle parts.jpg
Euro air box and collector that fits the box to the Webers. Straps to hold the air box to the collector.
Support Strut.
Gaskets to fit between the manifold and the air box.
Euro manifold.
Arm and pivot that fits linkage to manifold.(shown attached to manifold).
Gasket to fit Euro manifold to engine - but I think it's wrong
Part AR 65-81 Intake man gasket 99032000
Euro throttle arm
Throttle linkage arm with ball ends

What am I still missing?
 

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while the euro manifold is probably much better than the Spica setup ( I run that setup on a 2 liter) I'm guessing your jetting is not right causing the stumble.
 

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You did mentioned for a support strut, however, couldnt locate this in your photo. If this strut is missing might be your problem. I'm talking for the long strut goes all the way up from RH motor mount till the carbs. Keep also in mind that NOT all these struts/brackets were the same. You must have the correct one for your 1750cc, or, you need to modify one which is not the right for your engine. Not so rare, indeed, is that in case you have a shorter or longer bracket you can easily destroy your carbs to manifold mounts so to have leaks in there...If you dont have a reference so to measure if your strut is the right for your job,while everything is in order , just double check if the upper 2 holes of the support bracket are in line with the 2 holes of the euro air canister lower base and you must NOT use any special force to pass screws in the holes, If this is your case, strut is not the proper.My 2 cent
 

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It stumbles off idle, and the K&N's are just **** noisy. (does that mean I'm getting old? :confused:)
Nah, if you were getting old you wouldn't hear them :D Open intakes are loud...part of the job of the intake system is to act as a muffler for the front end of the engine.
 

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Great idea on the update and for sure get rid of the K&N which hits the frame, loosens the carbs from the spica manifold and sucks air as a result. I have one of each, and looks like you have the best parts except maybe a thermostat? A spica conversion actually works fine without the **** K&N filters. I don't recommend the cost of a full euro.

Here is a photo of my euro conversion, and the one problem I had was fitting a hose from the valve cover to the air box, as heater hose is too thick walled to clear a fitting on my intake. I had to remove the S shaped metal and hose shown in your current set up. Still working on that.
 

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Great idea on the update and for sure get rid of the K&N which hits the frame, loosens the carbs from the spica manifold and sucks air as a result. I have one of each, and looks like you have the best parts except maybe a thermostat? A spica actually works fine without the **** K&N's.

Here is a photo of my conversion, and the one problem I had was fitting a hose from the valve cover to the air box, as heater hose is too thick walled to clear a fitting on my intake. I had to remove the S shaped metal and hose shown in your current set up. Still working on that.
The euro carb setup has a vent from the cam cover with a 90 deg in it and uses a hose with a 90 deg to get to the air box.

What I did was found or machined a tube the same dimensions as the vent tube, cut a 45 deg on one end and cut a 45 deg on the vent tube and welded the new tube's 45 to the modified vent tube to get a 90 deg bend.

I think it ends up a little shorter and tighter than an original euro vent so do not waste any of the length of the FI vent tube when you cut the 45 there.

Ciao

Ken
 

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Thanks Ken, this is what I've been working towards and would love to see a picture of something that works. I'm having trouble finding suitable thin wall tubing. I had it once, but an Alfa expert modified it to use someplace else in the car when he upgraded from a 1300 style manifold to the 1750 style. . .:mad:
 

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Thanks Ken, this is what I've been working towards and would love to see a picture of something that works. I'm having trouble finding suitable thin wall tubing. I had it once, but an Alfa expert modified it to use someplace else in the car when he upgraded from a 1300 style manifold to the 1750 style. . .:mad:
I,m away sailing for a couple of weeks. will try and post a pic when I get back. I expect that I found a tube or pipe of suitable size the bored and turned OD to match the vent
.

FWIW

Ken
 

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Hey, sailing sounds great! I'm sure I can find some suitable material one of these days and make it look and function pretty well. I imagine Lokki will run into this too.

Thanks!
 

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Below is a pic of what I've gathered.... what am I missing?

Euro air box and collector that fits the box to the Webers. Straps to hold the air box to the collector.
Support Strut.
Gaskets to fit between the manifold and the air box.
Euro manifold.
Arm and pivot that fits linkage to manifold.(shown attached to manifold).
Gasket to fit Euro manifold to engine - but I think it's wrong
Part AR 65-81 Intake man gasket 99032000
Euro throttle arm
Throttle linkage arm with ball ends

What am I still missing?
As alfaroad wrote, you need that support strut that goes between the motor mount and the air box.

I don't see a bypass hose in your photo or on your parts list. Note that the bypass hose from the Spica manifold won't fit a Weber manifold. Centerline carries the correct part - it's their part # RH480.

I don't see a thermostat in your picture or on your parts list - I'm pretty sure that the style of Weber manifold you have takes the same thermostat as a Spica manifold, so you can use the one you have.

Why do you think your intake manifold gasket is wrong? The Weber manifold uses the same gasket that the Spica manifold does. I don't think those changed until the introduction of EFI in the 80's.

Your list says "Throttle linkage arm with ball ends". I assume you know this, but you need two throttle arms - a long one that runs horizontally, and a short one that runs vertically.

I don't see any flex mounts between the manifold and carburetors in your photo. Centerline carries two styles of these: you can use four WC106's, or two WC106's and one WC110 (which is what I'd recommend). See photos below. You'll also need eight gaskets for the flex mounts - these are Centerline part # WC107



 

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I do not see and you need a grounding cable to jumper across the rubber mounts to suppress static discharge that could lead to fuel fire

ken
 

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Discussion Starter · #13 ·
Thank very much, guys. I do have the support strut from the block to the air box... and I have a new thermostat. I have a bypass hose albeit with the problems RC mentions above.
I need the mounts, gaskets, and grounding strap.

Appreciate all this help. As this progresses, I'm sure I'll be back for more help.

Lokki
 

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I currently have the Spica conversion setup but I was wondering if the Euro setup would bring in the Webers closer to the engine. I have an awesome GTAm style ram air intake box I would like to use but need about 1/2" more room at the front.
 

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I,m away sailing for a couple of weeks. will try and post a pic when I get back. I expect that I found a tube or pipe of suitable size then bored ID and turned OD to match the vent.
.

FWIW

Ken
I guess I lost track of this thread so finally before I go sailing again here are a couple of pictures that produce a setup more like the original Euro.

I found a tube or pipe of suitable size then bored ID and turned OD to match the vent, cut two 45 deg angles on the vent and new piece and then welded the new piece to the vent thus producing a 90 deg vent to take the original Euro hose.

Hope this helps

Ciao

Ken
 

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I currently have the Spica conversion setup but I was wondering if the Euro setup would bring in the Webers closer to the engine. I have an awesome GTAm style ram air intake box I would like to use but need about 1/2" more room at the front.
Off the top of my head, I believe the answer is "no, the factory manifold won't bring the carbs appreciably closer to the head". The dimensions may not be identical, but I don't think they're different by as much as 1/2".
 
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