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Discussion Starter #1
I had occasion to be photographing a number 4 cylinder carb manifolds and thought I would share pics of variations that I have and ask others to fill in information as to application, years and add their photos of other variations.

I have divided the pics into early and late to distinguish between the manifolds with inline thermostat and those later ones with the drop in style. Maybe there should be 2 groups for early.

I list the casting mark, any casting changes I have noticed and the as cast inlet and outlet dimensions.

Pics 1 & 2: Early #_, Casting mark punched sideways: 3, Threaded on water distributor at rear, Ports: 45mm chamfer inlet/36mm outlet.

Pics 3 & 4: Early #2, Casting Mark inverted: [email protected], Now water distributor part of casting, Ports: 45mm Chamfer inlet/38mm outlet.
 

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Discussion Starter #2 (Edited)
Pics 5 & 6: Early #3, Casting mark Inverted: [email protected], Ports: 40mm inlet/32 outlet

Pics 7 & 8: Early #4, Casting mark inverted: [email protected], Now webs cast between ports, Ports: 40mm inlet/32mm outlet
 

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Discussion Starter #3
Pics 9 & 10: Late #1, Casting mark: @1, Ports: 40mm inlet/32mm outlet

Pics 11 &12: Late #2, Casting mark: @2…( note 3 dots after 2), Ports 40mm inlet/36mm outlet
 

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Discussion Starter #4
Pics 13 &14; Late #3, Casting mark :mad:3, Now webs between ports, Ports: 40mm inlet/ 36mm outlet

Yours in Alfas

Ken
 

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This is great info, Ken. I currently have an unmodified early #4 on my car, but since then I've acquired a late #6(?!?), which you don't have listed there. Any ideas what that might be? I think it's from a Euro 2L. Pic is attached

The motor is a nicely warmed over 2L with 10.4:1 pistons, Autodelta cams w/ 10.6 mm lift, and 40DCOE32s with 32mm chokes. I'm thinking the smaller ports on the early manifold are probably holding back the engine somewhat, so over the winter I plan on swapping over to the later manifold and possibly going to 33 or 34 mm chokes with appropriate jets / emulsion tubes / etc.

-Jason
 

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Discussion Starter #6
jarrington said:
This is great info, Ken. I currently have an unmodified early #4 on my car, but since then I've acquired a late #6(?!?), which you don't have listed there. Any ideas what that might be? I think it's from a Euro 2L. Pic is attached

The motor is a nicely warmed over 2L with 10.4:1 pistons, Autodelta cams w/ 10.6 mm lift, and 40DCOE32s with 32mm chokes. I'm thinking the smaller ports on the early manifold are probably holding back the engine somewhat, so over the winter I plan on swapping over to the later manifold and possibly going to 33 or 34 mm chokes with appropriate jets / emulsion tubes / etc.

-Jason
Hi Jason, thanks for your contribution. Can you measure the ports if it is as cast and can you determine any other differences from the other late manifolds I have listed.

Ciao

Ken
 

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kengta said:
Hi Jason, thanks for your contribution. Can you measure the ports if it is as cast and can you determine any other differences from the other late manifolds I have listed.

Ciao

Ken
How are you measuring? On the carb side the ports are chamfered, are you measuring from the face or where the chamfer ends in the bore? I assume on the head side you're measuring horizontally?

-Jason
 

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Carb Thread.

This is great information guys. I didn't know there was such a selection of manifolds. I hope you develope this thread a bit more and lets us all know where each of these manifold came from and what they'll fit. Thanks.
 

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Discussion Starter #9
jarrington said:
How are you measuring? On the carb side the ports are chamfered, are you measuring from the face or where the chamfer ends in the bore? I assume on the head side you're measuring horizontally?

-Jason
Jason,

On both sides I measured the maximum diameter at the face. 2 of my measurements were of chamfered units. Pehaps the diameter that the chamfer leads to is important and differs from casting to casting and usefull to have.

Ciao

Ken
 

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Hi Ken, finally got around to posting data on this manifold that I believe is from a 2L (but can't confirm certainly other than by it's shape) ;

-dimension at carb side chamfer 42.0 mm
-dimension at carb side 39.5 mm
-dimension at cyl head side 35.5 mm

000_0483.jpg
100_1000.jpg
100_1005.jpg

The thermostat cover on this unit is broken...anybody have any idea where I can get a replacement one?
 

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Early Weber Intake Manifold

Ken,

These Are Photos Of The Intake Manifold We Have Been Talking About In Another Thread (items for sale). It Has A Rough (sand cast?) Finish, A Sideways #2 Stamped In The Center, Has Head Ports Measureing 37mm X 48mm (I am measuring the head side ports vertically & horizontally as that is how alfa did it in their "PERFORMANCE OPTIONS CATALOGUE") & Carb Ports Measuring 40mm Chamfering Out To 45mm. These Measurements Match Up With Intake Manifold #10502.01.060.02 ("1600 105's") Listed In The Above Catalogue. As You Can See This Manifold Matches Up Well With Your First Manifold Shown "man 4" (in fact I can't see any differences between my stamped #2 and your stamped #3 manifold). You Should Measure Your "man 4" Head Side Ports As Alfa Did (vertically & horizontally) To See If There Is A Difference As The Options Catalogue Also Shows Head Ports Of 31mm X 40mm (#10516.01.060.02) And 38mm X 49mm (#10502.01.060.01 & #10532.01.060.00).

-John
 

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Discussion Starter #13 (Edited)
Ken,

These Are Photos Of The Intake Manifold We Have Been Talking About In Another Thread (items for sale). It Has A Rough (sand cast?) Finish, A Sideways #2 Stamped In The Center, Has Head Ports Measuring 37mm X 48mm (I am measuring the head side ports vertically & horizontally as that is how alfa did it in their "PERFORMANCE OPTIONS CATALOGUE") & Carb Ports Measuring 40mm Chamfering Out To 45mm. These Measurements Match Up With Intake Manifold #10502.01.060.02 ("1600 105's") Listed In The Above Catalogue. As You Can See This Manifold Matches Up Well With Your First Manifold Shown "man 4" (in fact I can't see any differences between my stamped #2 and your stamped #3 manifold). You Should Measure Your "man 4" Head Side Ports As Alfa Did (vertically & horizontally) To See If There Is A Difference As The Options Catalogue Also Shows Head Ports Of 31mm X 40mm (#10516.01.060.02) And 38mm X 49mm (#10502.01.060.01 & #10532.01.060.00).

-John
John thanks for posting here.

My #3 Stamped manifold has a head side port measurement of 38mm X 49mm so maybe (#10502.01.060.01 & #10532.01.060.00).


My manifold does not have the tapped hole into #1 port as does yours. It also has a number 1 stamped in the area circled in green. Picture is of your manifold. My #3 manifold also has some over stamping in the area of the #3 stamp.

BTW: I am not claiming my stamped #3 manifold is from GTA. I don't know where it came from. Maybe a Carlisle swap meet years ago.

My GTA 1600 head on 752507 is large port and has a ported matched later style 1600 manifold (casting mark 3, so no screw in elbo at firewall end). 2 other 1600 GTA heads I had, used on top of GTAj engines by Bruce Perry, were sleeved to small port and had matched ported later style 1600 manifolds. But these all would have been later North American mods I suspect as both were raced well into the 1970's.

Ciao

Ken
 

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Discussion Starter #14
From the early GTA parts Book 10/1965.

GTA Manifold 105.02.01.060.02 with Raccordo (bypass Elbo)
 

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Discussion Starter #15
From Later GTs/GTA parts Book unknown date .

GT, GTC & GTV Manifold 105.02.01.060.02

GTA Manifold 105.32.01.060.00
 

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Discussion Starter #16
From TI, SUPER, & TI SUPER parts book 9/67
 

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Ken,

I Just Looked Closely At My Manifold And It Has "1" Stamped At The Base (your lower left green circle) But Nothing At Your Upper Right Green Circle Location. In Addition, Was The Threaded Port (at number 1) Always There Or Added Later?

-John
 

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Discussion Starter #18
From 1600 Spider (Duetto) parts Book 3/67 pub 1251 and update 10/68 as in 3rd picture.
 

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Discussion Starter #19
From GT 1300 Junior parts book 1/70 Pub. 1516
 

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Discussion Starter #20
Ken,

I Just Looked Closely At My Manifold And It Has "1" Stamped At The Base (your lower left green circle) But Nothing At Your Upper Right Green Circle Location. In Addition, Was The Threaded Port (at number 1) Always There Or Added Later?

-John
I think that hole is present in most manifolds and usually has a hose barb in it as seen below. This would likely be blocked /plugged in race applications.
 

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