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Trained (ex)Professional, , 1953-2018 RIP,
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Sorry for the bit of off topic here. I've always been curious as to which model DCOEs were fitted to which model Alfa. Here's what I found;

40 DCOE 2 - Giulia Spider Veloce & Sprint Veloce, Sprint Speciale and Sprint Zagato
40 DCOE 4 - Giulia Sprint GT and GTC
40 DCOE 24 - Giulia Super up to mid 1967
40 DCOE 27 - Giulia Sprint GT Veloce, Spider 1600 (Duetto) and Giulia Supers from mid 1968 on
40 DCOE 28 - GT 1300 Junior, Spider 1300 Junior and Junior Z
40 DCOE 32 - 1750 and some 2000 GT Veloces
40 DCOE 33 - Giulia Supers from mid 1967 to mid 1968
45 DCOE 14 - GTA
45 DCOE 18 - GTA 1300 Junior

The prefix number is the barrel diameter in millimeters. 'DC' is doppio corpo or double throat, 'O' is orizzontale or horizontal and 'E' means the carb body is diecast. The suffix number indicates a specific combination of jet/venturi sizes.
 

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Thank s for posting this Jim, that really helps to identify what we have:)
The OE jet/venturi size for the 45's on the GTA JR. of 18 vs 14 for the GTA is interesting and stands out the most to me. I assume that due to the 1300's motor desire to rev it craves more air at higher RPM's for some upper rpm range HP is why they went with a 18 jet/venturi.

(Same goes with the comparision between the 40 DCOE 32 - 1750 and some 2000 GT Veloces
40 DCOE 33 - Giulia Supers from mid 1967 to mid 1968)

Sorry for the bit of off topic here. I've always been curious as to which model DCOEs were fitted to which model Alfa. Here's what I found;

40 DCOE 2 - Giulia Spider Veloce & Sprint Veloce, Sprint Speciale and Sprint Zagato
40 DCOE 4 - Giulia Sprint GT and GTC
40 DCOE 24 - Giulia Super up to mid 1967
40 DCOE 27 - Giulia Sprint GT Veloce, Spider 1600 (Duetto) and Giulia Supers from mid 1968 on
40 DCOE 28 - GT 1300 Junior, Spider 1300 Junior and Junior Z
40 DCOE 32 - 1750 and some 2000 GT Veloces
40 DCOE 33 - Giulia Supers from mid 1967 to mid 1968
45 DCOE 14 - GTA
45 DCOE 18 - GTA 1300 Junior

The prefix number is the barrel diameter in millimeters. 'DC' is doppio corpo or double throat, 'O' is orizzontale or horizontal and 'E' means the carb body is diecast. The suffix number indicates a specific combination of jet/venturi sizes.
 

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I do have some Weber DCOE 40's "made in Italy" but I want to trade them for some 45 DCOE's. If I hear of any others for sale I wll let you know.
 

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Trained (ex)Professional, , 1953-2018 RIP,
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FWIW, carburated Autodelta 1300 GTAjuniors usually had 45DCOE14's fitted rather than the 45DCOE18's.
Interesting. The only jetting difference between the two carbs is the main jet; 120 for the DCOE 18 and 135 for the DCOE 14. All other jetting, as well as the venturis (30mm), are the same.
 

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Interesting. The only jetting difference between the two carbs is the main jet; 120 for the DCOE 18 and 135 for the DCOE 14. All other jetting, as well as the venturis (30mm), are the same.
FWIW, carburated Autodelta 1300 GTAjuniors usually had 45DCOE14's fitted rather than the 45DCOE18's.
Maybe for the "Stradale 1300 GTA" they realized they did not need the larger jets. Interesting indeed.
 

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Richard Jemison
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Where does this crap come from????

The prefix number is the barrel diameter in millimeters. 'DC' is doppio corpo or double throat, 'O' is orizzontale or horizontal and 'E' means the carb body is diecast. The suffix number indicates a specific combination of jet/venturi sizes.
Thank s for posting this Jim, that really helps to identify what we have
The OE jet/venturi size for the 45's on the GTA JR. of 18 vs 14 for the GTA is interesting and stands out the most to me. I assume that due to the 1300's motor desire to rev it craves more air at higher RPM's for some upper rpm range HP is why they went with a 18 jet/venturi.

That is just so incorrect.
The carbs below (from previous list had different "AVs" Emulsion tubes idle jets etc. etc. along with the Venturi /jets I list for you. The last "code" # is simply the production model #.
Jim, for God`s sake don`t misinform this kid. He believes everything he reads!



FYI: try below as correct information::p
40 DCOE 2 - Giulia Spider Veloce etc. 29mm vent. 110/200 main/AC jets
40 DCOE 4 - Giulia Sprint GT and GTC 30mm vent. 127/220
40 DCOE 24 - Giulia Super 27mm 110/180
40 DCOE 27 - Giulia Sprint GT Veloce,27mm 110/180
40 DCOE 28 - GT 1300 Junior, Spider,28mm 112/210
40 DCOE 32 - 1750 and some 2000 32mm 130/200
40 DCOE 33 - Giulia Supers 27mm 110/180
45 DCOE 14 - GTA 30mm 135/220
45 DCOE 18 - GTA 1300 Junior 30mm 120/220
 

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Richard Jemison
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Here`s your answer

I'm curious to learn what you think is mis-information
The suffix number indicates a specific combination of jet/venturi sizes.
Your statement:rolleyes:.
And then that kid pops up with:
Thank s for posting this Jim, that really helps to identify what we have
The OE jet/venturi size for the 45's on the GTA JR. of 18 vs 14 for the GTA is interesting and stands out the most to me. I assume that due to the 1300's motor desire to rev it craves more air at higher RPM's for some upper rpm range HP is why they went with a 18 jet/venturi.

:p:p:p:p:p
 

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Trained (ex)Professional, , 1953-2018 RIP,
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The suffix number indicates a specific combination of jet/venturi sizes.
Your statement:rolleyes:.
So this is incorrect information? If so, would that mean then that one could have ordered a new Weber, say, a 40 DCOE 32, with different jet/venturi combinations? That would seem to contradict your post #10 which lists specific jet/venturi combinations for a specific model carb. I'm confused. :confused:

Or are you referring to RossoGTV4Me simply misinterpreting the information?
 

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Richard Jemison
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Gezzzz

Those listed by the Carbs are only the venturis and jets used by Alfa in those carbs:rolleyes:,.
The same carbs were used by Fiat,Simca, BMW ETC. The last numbers as I said were Production Numbers. What`s so hard to understand??
 

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Jim and Richard, may I suggest that we put a stop to the argument and help Giuliaguy locate a set of DCOE2s? Know that both of your wealth of knowledge is highly appreciated by the rest of us.

I have ONE DCOE2 that may be up for trade if someone happens to have a DCOE18 in decent condition.
 

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Trained (ex)Professional, , 1953-2018 RIP,
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Okay, I'm back.

In an effort to provide accurate information, I just spent a few hours pouring over numerous Alfa published documents as it pertains to venturi and jet sizes. Pasted below is the 40 DCOE application list as I originally posted it (with an addition of a separate 40 DCOE 27 listing as fitted to the mid 1968 on Supers). Added to this list, after each car model listing, are the venturi & jet sizes listed in post #10 of this thread as being correct for each application. If the Alfa published venturi/jet sizes differ, they are then listed in bold. Lastly is the source from which this information was obtained.


40 DCOE 2 - Giulia Spider Veloce & Sprint Veloce, Sprint Speciale and Sprint Zagato - 29mm venturi (V), 110 main jet (M), 200 air corrector (A) - 30V, 120M summer/115M winter, 180A - Spider Veloce & Sprint Special Tech Specs (TS) #1159 dated 3/66.

40 DCOE 4 - Giulia Sprint GT and GTC - 30V, 127M, 220A - 127/3M. This jet was fitted with a ball. However, it was discovered that this ball may stick resulting in drivability issues. So Alfa issued Information Sheet (IS) #1.05.124 dated 9/66 changing the original 127/3 main jet to a 1225 main jet without ball.

40 DCOE 24 - Giulia Super up to mid 1967 - 27V, 110M, 180A - Owners Manual (OM) #1231 dated 7/67.

40 DCOE 27 - Giulia Sprint GT Veloce, Spider 1600 (Duetto) and Giulia Supers from mid 1968 on - 27V, 110M, 180A - 30V, 120M (EXCEPT Giulia Super) - Spider 1600 OM #1165 dated 6/66.

40 DCOE 27 - Giulia Super from mid 1968 on - 30V, 117M, 180A - TS #1719 (supplement to TS #1133).

40 DCOE 28 - GT 1300 Junior, Spider 1300 Junior and Junior Z - 28V, 112M, 210A - 220A - GTJ Series 1 OM #1219 R1 dated 10/67, GTJ Series 2 OM #1490 dated 11/69 and Junior Z OM #1528 dated 11/69. However, GTJ Series 3 OM #1659 dated 2/71 and Spider Junior 1.3/1.6 OM #1892 dated 5/72 lists an air corrector size of 210.

40 DCOE 32 - 1750 and some 2000 GT Veloces - 32V, 130M, 200A, correct for Series 2 1750s, 1750 OM #1553 dated 2/70 - Series 1 1750s however have a 125M - 1750 OM #1373 dated 7/68.

40 DCOE 33 - Giulia Supers from mid 1967 to mid 1968 - 27V, 110M, 180A - 30V, 120M, 200A - OM #1290 R1 dated 10/67. It should be noted that Technical Service Bulletin (TSB) #04.69.3.2 dated 9/69 states that a change was made to the accelerator pump jet, accelerator pump inlet jet and the accelerator pump spring.

45 DCOE 14 - GTA - 30V, 135M, 220 - OM #1063 dated 6/65

45 DCOE 18 - GTA 1300 Junior - 30V, 120, 220 - OM #1360 dated 6/68 (supplement to OM #1219).

During the course of this research, I discovered that the 45 DCOE 14 could also have been fitted to the Giulia TI Super as special equipment. However, unlike the 30V, 135M & 220A as fitted to the GTA, the Giulia TI Super application was fitted with 30V, 120M summer/115M winter and 180A. This information comes from service manual #1008 R3 dated 5/73. This would mean then that Weber's statement, 'it is always possible to identify the main calibrated parts of a carburetor' (calibrated parts meaning jets/venturi of a specific value) by the carb's model/type designation may not be without exception. However, what I don't know is;
1) Did Alfa request that Weber re-jet a 45 DCOE 14 carb or
2) Did Alfa purchase 45 DCOE 14 carbs and re-jet them themselves.

I though to add the following 40 DCOEs to the above list.
40 DCOE 44/45 - 00526 & 00536 1600cc engines - 30V, 117M, 180A.
40 DCOE 76/77 - 2000cc engines - 32V, 135M, 210A.
The above two listings come from TSB #04.73.2.2 dated 5/73 that deals with emission control engines.

Of course, the possibility exists that there may be Alfa published documents that may have revised any of the above listings. If anyone has such a document(s), I would be most interested in obtaining a copy. :)
 

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I was skimming through John Passini's Weber books this morning. He writes about differences in the progression holes on different 40DCOE's. In particular the 40DCOE31 is very different from the mainstream, but it was not used by Alfa Romeo. I wonder if there are significant differences between the ones that we are more familiar with.
 

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Jim, Great wealth of info!

Question for you all. I am looking at 40 DCOE "72" and "73" (suffix number indicates a specific combination of jet/venturi sizes). Anyone have any info on the 72 & 73 jet venturi sizes on these 40 DCOE's. I had planned to use these on a modified 2L for time trials...Input appreciated!
Okay, I'm back.

In an effort to provide accurate information, I just spent a few hours pouring over numerous Alfa published documents as it pertains to venturi and jet sizes. Pasted below is the 40 DCOE application list as I originally posted it (with an addition of a separate 40 DCOE 27 listing as fitted to the mid 1968 on Supers). Added to this list, after each car model listing, are the venturi & jet sizes listed in post #10 of this thread as being correct for each application. If the Alfa published venturi/jet sizes differ, they are then listed in bold. Lastly is the source from which this information was obtained.


40 DCOE 2 - Giulia Spider Veloce & Sprint Veloce, Sprint Speciale and Sprint Zagato - 29mm venturi (V), 110 main jet (M), 200 air corrector (A) - 30V, 120M summer/115M winter, 180A - Spider Veloce & Sprint Special Tech Specs (TS) #1159 dated 3/66.

40 DCOE 4 - Giulia Sprint GT and GTC - 30V, 127M, 220A - 127/3M. This jet was fitted with a ball. However, it was discovered that this ball may stick resulting in drivability issues. So Alfa issued Information Sheet (IS) #1.05.124 dated 9/66 changing the original 127/3 main jet to a 1225 main jet without ball.

40 DCOE 24 - Giulia Super up to mid 1967 - 27V, 110M, 180A - Owners Manual (OM) #1231 dated 7/67.

40 DCOE 27 - Giulia Sprint GT Veloce, Spider 1600 (Duetto) and Giulia Supers from mid 1968 on - 27V, 110M, 180A - 30V, 120M (EXCEPT Giulia Super) - Spider 1600 OM #1165 dated 6/66.

40 DCOE 27 - Giulia Super from mid 1968 on - 30V, 117M, 180A - TS #1719 (supplement to TS #1133).

40 DCOE 28 - GT 1300 Junior, Spider 1300 Junior and Junior Z - 28V, 112M, 210A - 220A - GTJ Series 1 OM #1219 R1 dated 10/67, GTJ Series 2 OM #1490 dated 11/69 and Junior Z OM #1528 dated 11/69. However, GTJ Series 3 OM #1659 dated 2/71 and Spider Junior 1.3/1.6 OM #1892 dated 5/72 lists an air corrector size of 210.

40 DCOE 32 - 1750 and some 2000 GT Veloces - 32V, 130M, 200A - 125M - 1750 OM #1373 dated 7/68.

40 DCOE 33 - Giulia Supers from mid 1967 to mid 1968 - 27V, 110M, 180A - 30V, 120M, 200A - OM #1290 R1 dated 10/67. It should be noted that Technical Service Bulletin (TSB) #04.69.3.2 dated 9/69 states that a change was made to the accelerator pump jet, accelerator pump inlet jet and the accelerator pump spring.

45 DCOE 14 - GTA - 30V, 135M, 220 - OM #1063 dated 6/65

45 DCOE 18 - GTA 1300 Junior - 30V, 120, 220 - OM #1360 dated 6/68 (supplement to OM #1219).

During the course of this research, I discovered that the 45 DCOE 14 could also have been fitted to the Giulia TI Super as special equipment. However, unlike the 30V, 135M & 220A as fitted to the GTA, the Giulia TI Super application was fitted with 30V, 120M summer/115M winter and 180A. This information comes from service manual #1008 R3 dated 5/73. This would mean then that my 'the suffix number indicates a specific combination of jet/venturi sizes' is incorrect since each model carb could have been fitted with different internal components. So my apologies for this error.

I though to add the following 40 DCOEs to the above list.
40 DCOE 44/45 - 00526 & 00536 1600cc engines - 30V, 117M, 180A.
40 DCOE 76/77 - 2000cc engines - 32V, 135M, 210A.
The above two listings come from TSB #04.73.2.2 dated 5/73 that deals with emission control engines.

Of course, the possibility exists that there may be Alfa published documents that may have revised any of the above listings. If anyone has such a document(s), I would be most interested in obtaining a copy. :)
 

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40DCOE72/73 were fitted to European 1.8 Alfetta's. 32 venturi, 4.5 AV, 135 main, 55F17 idle, F34 ET, 210 AC
 
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