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Discussion Starter · #1 ·
Greetings. I ordered the set of '74 GTV 2.0 stock exhaust manifolds from a used parts place. Photo attached. I am not sure these are what I am looking for as people have told me that the '74 stock manifolds were two pieces, 1 piece for cylinders 1 and 3, 1 piece for cylinders 2 and 4. What I received appears to be 1 piece for cylinders 1 and 4, 1 piece for cylinders 2 and 3. The whole reason I ordered these is to improve mid range torque in my '88 Spider. Please advise as to whether these are the best early '70's 2.0 liter stock manifolds for mid range performance. Thank you for your help. --John
 

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1/4 & 2/3 is the correct configuration Never seen a 1/3 & 2/4 on a stock system
 

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Greetings. I ordered the set of '74 GTV 2.0 stock exhaust manifolds from a used parts place. Photo attached. I am not sure these are what I am looking for as people have told me that the '74 stock manifolds were two pieces, 1 piece for cylinders 1 and 3, 1 piece for cylinders 2 and 4. What I received appears to be 1 piece for cylinders 1 and 4, 1 piece for cylinders 2 and 3. The whole reason I ordered these is to improve mid range torque in my '88 Spider. Please advise as to whether these are the best early '70's 2.0 liter stock manifolds for mid range performance. Thank you for your help. --John
John, I think I see part numbers cast in. Provide those numbers (different for each piece) and a picture of the other (top) side of the manifolds.

Then we will know for sure. Plus you can provide a measurement across the port where they bolt to the head.

ciao

Ken
 

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71 Berlina 74 GTV 17 Giulia Q4
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You got the correct ones, they should make your motor a lot happier!
 

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'66 Sprint GT, '67 Duetto, '70 BMW 2800CS
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people have told me that the '74 stock manifolds were two pieces, 1 piece for cylinders 1 and 3, 1 piece for cylinders 2 and 4.
That's the last thing you would want. Remember, the firing order is 1-3-4-2. So having 1&2 share a header and 3&4 share a header would have consecutive firing cylinders competing for the the header's capacity. Alfa engineered it right (as usual) by pairing cylinders that fire 360 degrees apart.
 

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71 Berlina 74 GTV 17 Giulia Q4
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360 degrees apart?
 

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'66 Sprint GT, '67 Duetto, '70 BMW 2800CS
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360 degrees apart?
Perhaps it would have been clearer if I had written: "by pairing cylinders that fire 360 degrees of crankshaft rotation apart".

In contrast, john802's proposed 1&2 and 3&4 configuration would have paired cylinders that fire 180 degrees of crankshaft rotation apart.

Make sense?
 

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71 Berlina 74 GTV 17 Giulia Q4
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Yes, it was more tongue in cheek than anything else.
 

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They are definitely correct .........NOTE....Check carefully for cracks especially around webbed area the cracks can be very fine and open up with heat.
 

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Discussion Starter · #16 ·
Well, I sent the exhaust manifolds out to be ceramic coated. The shop found a crack, see photo below. So glad I sent them out to be coated. You could not see the crack with all of the rust on them before they were sand blasted.
 

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PM me
 
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