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Which DCOE’s, new Spanish or old Italian?

bfeng

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It’s time to get a set of three 45 DCOE’s. New Spanish made units are avail for about $400/ea fro Pierce Manifolds.

A friend of mine recently acquired a set of like new 46 year old Italian made u it’s (Type 15&16). This type has two large progression holes and obviously no air bypass circuit. They look to have less than 5-10k miles of use (zero gas staining anywhere, all hardware looks as new, barrels clean and throttle plate alignment is very good).

I’m looking for opinions on reasons to go with new Spanish vs with old Italian DCOE’s.
 
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jmackro

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The lore is that the Italian-made DCOE's are of higher quality than the Spanish-made. Whether this is true, or just nationalistic chauvinism might be debated. But if it were me, I'd go for the ones made in Bologna.
 

Stevehose

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Are these going on your coupe? I’d go reconditioned Bologna but not with 2 progression holes unless you’re racing. I can send you Gabriele’s info, he is Alfa1750 on ebay and has an internet shop called Carburatori Italia. He offers several different styles reconditioned. I got my italian DCOM from him, they are later model dcoe with adjustable accel pumps, idle air bleeds, and vacuum ports. I think you can find dcoe 153 italian before they went to spain, these have vac and bleeds.
 

bfeng

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Yes, these would go on my restored B9 motor/trans and LSD. Plus an Alpina triple carb air box system that someone replaces with EFI, and Stahl headers (couldn’t find any Alpina headers).

I’m not yet convinced the Spanish ones are worse mfg, but perhaps not as meticulously assembled (we were comparing butterfly gaps).

I’m leaning away from the new versions with air bypass circuit because they require a bit more clearance around the thermo housing. Seems like a petty objection though.

Progression holes: yes, only 2 holes seems crude. An E9 needs to be more refined than a forty GTV. I’ve always used the tipo’s with three and had zero problems with flat spots and uneven transition. But I also don’t max out the Venturi size (which makes the tuning much more finicky). Everyone says you can drill new progression holes as needed, but I’ve never done it myself.
 

m5bb

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What Steve says.
I have the 152 Spanish version and with Steve's help they are running pretty good. 45's are big for a stock 3.0 or even a 3.5 motor. My motor is not stock. I used them but had to change the venturi's to get any kind of low speed. They have to have some air moving to work properly. Don't remember the venturi size but have notes on all the jetting and sizes if you need them. BTW Pierce has a chart you can download to keep all you specs on. Pretty handy.
Gary
 

stphers

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If you really want some good info on Webers, progression holes and the differences between Spanish and Italian carbs, have a look at some of the discussions on the AlfaBB ( Alfa Romeo forum ) I thought that I knew a lot about webers but after going through some of the posts on the Alfa site, I have learned a great deal. There are a number of very indepth threads there about everything you wanted to know ( and not know ) about Weber carbs Check out Gordon Raymond's posts, he is a Weber guru.

Thanks, Rick
 

bfeng

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Gary, Rick

Thanks for the advice.
The motor is a 3.5 M90 that Mario built (Stage 1.5). He said it’s over the threshold where 45’s make sense. Good to know the Spanish made Weber’s work fine.

John

Rick: I know Crater and Taylor are on Alfabb. What Alfa do you have.
 

stphers

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I have a 69 Spider Veloce, Canadian car, which means that it is a euro car, I am third owner. and it is not red It is green. Waiting in line at my hobby shop to get worked on. Between customers cars and my kids cars , I don't get as much time as I would like to do my own restorations.
 

bfeng

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Ah, the Duetto (and 1969 1750 spider) were what got me interested in Alfa’s 40 years ago. But I opted for a 1974 coupe because once in a while I’d like to stay dry on a long tour. I specifically looked for a non-red Alfa and ended up with Lemans Blue. It just got dropped off at a shop for an unneeded bare metal repaint last Saturday. I've been in queue since last September... good shops are hard to find

John
 
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