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Discussion Starter #1
it's decision time. the solex 35 sat for at leat ten years, and then suffered a couple of good backfires this afternoon. it's now leaking enough fuel externally to be a fire hazard. quick and relatively easy would be...get a new dgv36, bolt it on, figure out the throttle linkage, and go.

or, not quick, easy, or inexpensive....find a euro manifold, a couple of sidedrafts, support plates, veloce engine mounts, exhaust manifolds,etc.

i had a bad experience with a new pair of spanish dcoe40s on a 2l in a previous car. any feedback on the dgv, good or bad?

or, check these out. NEW! Old Stock - Matched Pair Italian Weber DCOE NOS | eBay

any thoughts on running these on a 1750? thanks all. jamie
 

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Or choice C would be to take your carb to someone who knows what they are doing and have it fixed.......

I would go with C...
 

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MANY years ago I ran a pair of 38DCOE's from a Ferrari engine on the 1750 transplanted into my Alfa SS. The car was originally a 1300 and the P.O. had blown that engine, and junked the remains, selling the SS incomplete. I needed it to run to sell it, so used a 1750 with the Webers I had on hand. As I remember, the combination worked just fine. I think I had 32 mm chokes in the 38's.
However, as mentioned above, there are easier and less costly ways to solve your problem.
 

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Discussion Starter #4
thanks for the input. 101/105 guy is right, i'm not rebuilding carbs. i'll take 'em off and bolt 'em back on, but i generally leave them alone otherwise. i hope to get some power out of this engine at some point, but i'm hoping to drive the car before it's perfect. i've gone through the brakes, [ retained the 2 shoe fronts] installed centerline yellow springs and bilsteins, and new u joints, wheel bearings and seals, mounted a set of vredestein sprint classics on the newly powdercoated wheels.
my goal is a fast street/trackday car. george willet tells me i'll probably be happy with a well set up single 2 barrel engine, and i don't doubt him. but like so many of us, i'm drawn like a moth to to the idea of that pair of webers..
 

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find a euro manifold, a couple of sidedrafts, support plates, veloce engine mounts, exhaust manifolds,etc.
You don't have to install veloce engine mounts and a veloce exhaust manifold in order to run dual Webers. You just need that stuff if you want to run the original Veloce air horns. I have Webers in my 101 abnormale with Weiand air filters. Yea, they're noisy (but I like the sound!) and no, it doesn't look stock (like I care) - but it does fit OK.

I'm not saying you should do this. Maybe fixing your stock setup would be cheaper / better / more original / etc. All I'm saying is that a complete veloce setup isn't mandatory for dual Webers.
 

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Discussion Starter #6
that's a great looking engine bay! i had no idea the carbs would fit without canting the engine.i'm not too worried about originality, this isn't a veloce. food for thought. thanks.
 

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I'd skip the 38DCOEs. Not really appropriate for a 1750. They were used on 1,100cc engines. Of course the engine would run, and make plenty of torque, just nothing near its max horsepower capability. It would start to run out of air at a much lower RPM than expected and give the impression of a sick engine.

Just buy a good pair of 40DCOE's from Alfa1750 in Italy, find a manifold and gin up some air cleaners and support rod. Easy enough to do, and all the jetting is well understood for that engine. Heck, I've got a Weber manifold I'd sell. I don't recall if it is 1600, 1750, or Euro 2l, but suspect it is a 105 unit of some sort.
 

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Discussion Starter #8
thanks for the insight on the 38s. i found alfa1750s ebay store. he's not showing any dcoes, but has a pair of dcom 40s. supposed to be an evolution of the dcoe, and interchangeable. i sure don't know. anyone used 'em?
 

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Yes, they can be converted to DCOE's with some work. They are a emission variation.
You might be better off looking on e-bay or checking with those that sell such things used like Dean Russell at Trail Auto, Karen McGowan , Hotlegs on the BB,m or Keith Goring at Alfa's Unlimited. I restore and rebuild DCOE series and have several used ready to rework, but will be out of town several weeks. Ask any of those I referenced above about the quality of my work if you wish.
Good Luck!
 

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Discussion Starter #10
well, i just removed the solex. and it seems the gasket sets are in short supply. alfa parts can't get them. centerline is out of stock, as is iap. so much for the quick fix.
 

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Discussion Starter #11
i forgot to thank you, gordon,and you, don, for your thoughtful suggestions. i'm going to check around locally to see if i can round up a pair of carbs and a manifold. if you i'm not successful, i will be in touch. i'm heading back to work [ on a boat, in the bering sea ] on the 22nd, so if i seem to be more impatient and in a bigger hurry than your average bear, it's partly 'cause i have relatively short bits of time to get things done on the car. if you're heading out for vacation or travel, gordon, enjoy.
 

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Fishy,

Gordon's last reply might be misinterpreted. The 40DCOM cannot be converted to be a DCOE. The DCOE uses a piston type accelerator pump and the DCOM uses a diaphragm. Furthermore, the DCOM has a differently configured idle and transition circuit. Lastly, the DCOM was delivered with different emulsion tubes than the DCOE, having integral air corrector holes rather than replaceable air corrector jets.

Having said all that - I am using 40 DCOM carbs on my 102 Roadster, although it is a Alfa/FNM 2300 engine. So far, I've been very impressed with the DCOM carbs, and what little I've found published about them is complimentary. I had some issues - and still do - but have confidence they'll be sorted out eventually.

Alfa1750 should have DCOEs in stock. I'd be quite surprised if he doesn't. Be sure to specify good Italian carbs rather than the later Spanish-made units. If he has DCOM's, then that will be fine. He can provide them with jetting that should work for you as-delivered. The ones he shipped to me had later or modified emulsion tubes able to accept individual air-corrector jets. I'm still sorting out the idle jets, but it has good driveability as is.

As I noted, let me know if you're interested in my intake manifold. Just check around and find out what they're going for and that'll be OK with me. I have no recollection of what I paid for it.
 

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You are right Don. I should have stated they can be made to function much like DCOE's, rather than "converted". My term converted has to do with jetting and chokes. My experience with DCOM's is positive as well, it just needs a little "set-up".
 

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There is a shortage of information on the DCOM. I've read more than once that the idle circuit is fed from the main-jet stack, and has 6 transition holes. It is said to run very rich unless one uses the idle jets specifically for the DCOM.

When I first installed my DCOMs it had 59F21 idle jets. I couldn't get it to idle at all. After messing around with quite a variety of classic DCOE idle jets that worked OK, I reinstalled the 59F21 units today. It was clear that the air-bleed hole in the F21 was larger than in the F8 or F9 jets, so should lean out the transition range a bit. My gas mileage has not been good, presumably due to the rich around-town power band.

I got it to idle OK by opening up the idle screws waaaaay out. My goal was to get rid of the rich popping that I've been getting on deceleration, as well as what seems to be a slight richness during transition-hole operation - like around town driving. After one test drive, the low-speed cruising seems better, but the popping during deceleration is still present. I thought I had the butterflies well synchronized, but will revisit that soon.

Point being - the DCOM definitely has some peculiarities in the idle/transition circuit different than the DCOE. Not sure where to go from here. I still think it's a good carb, though.
 
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