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We picked up two from Dave in AZ last month. I still haven't taken them apart to see what jets and whatnot they have but I'll be doing that soon. Maybe tonight.

Here they are as seen in tonight's dress rehearsal.



So pretty!

We plan to use these in our Bonneville adventure, but time is running out. I need to start getting parts now, starting with rebuild kits, jets, air filters, linkage, and other stuff.

John at EGR has offered to dyno tune the car for us, possibly bartering for web site work. Even so, I need to know more and will be studying up on them. I've read a bit here and I've got a Weber book. I've also got a good resource in Sacramento for questions. He's offered to help with our intakes. (Carters)

So what I'll be asking for here is help with specific stuff. I hope I don't overwhelm you, but I really would appreciate some feedback. In return I'll keep posting our progress, and failures, here for future generations to enjoy. I'll try to make this as useful as possible for others.

Most my questions now are about parts. I'll have tuning questions later.

But first, some details about our motor:
  • 2.0L (1.9 L block. This is Ford Cook's old motor.)
  • high-compression pistons
  • Torquer cam.
  • Header from OGTS.
  • Compression?
  • Valves, larger valves, hardened seats, head not ported.
So here are the questions:

Compression
How exactly do I measure this? Pipette some water into the head to measure the volume then do the math? Of mash modeling clay in there, pull it out and weigh it, and from the density get the volume, then do the math? I guess I can Google this one.

Linkage
Our carbs came with the linkage that connects them to each other, but we need the cable kit to connect them up with the throttle. Will this work?

Link: UNIVERSAL CABLE KIT

Sorry, they don't have pictures for a lot of their stuff. This is their universal cable kit.

I expect I'll need to make a bracket or two, but is this kit the correct starting place?

Rebuild Kit
This what I plan to get.

Link: 40,45 DCOE Rebuild Kit

This one does not seem complicated. Any comments?

Jets
I'm sure I'll need one of these kits.

Link: Performance Main and Air Jet Kits

The 737-240 looks like the one for us.

John (EGR) told me I need to bring jets that are above and below what I expect I'll be using.

Air Filters
These are what I'm looking at.

Link:DCOE 40 42 45 48 K&N Air Filter Kit

These are a bit pricy. I think I saw them for about half that price on another site. I saw the little sock-style air filters but I don't think that's what we'll need.

Link: WK40 - Uni Filter Sock Filter 40 DCOE

We plan to cut out the heater box to make room for them.

Gaskets and Thermal Isolation
This is what I have found. Seems they don't sell maple wood thermal isolators. ;)

Link: DCOE SOFT MOUNT KIT

Tools
I used to have these when I had a dual SU carbureted Volvo.

Link: Carburetor Synchronizer

Comments? I know there are cheaper Bug units, and I've seen a very clever home-built manometer.

Other
Alan just got back from Monterey and got to talk to an Opel GT guy who had dual DCOEs. He highly recommends bracing everything. That's a lot of cantilevered mass hanging off the side of the motor. Vacuum leaks, if not actually breaking something, would be expected without doing this. The recommendation was:

1. Make a bracket out of sheet steel that will connect the carbs, at the horns together so they act more like one single carb as far as vibration goes.
2. Extend a support to the motor mount to stabilize them.

Comments?

My sources so far are RedlineWeber and WeberCarbsDirect.
 

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Discussion Starter #2
I've take one apart. It needs cleaning but it doesn't look bad. Certainly not full of rat **** and olive pits, like our original carburetors.

Some numbers:

Model: 40DCOE151, made in Italy.
No. 9C
Choke: 32 (Is this also called the venturi tube?)
Main jet: 120
Air corrector: 170
Emulsion tube: F11
Idle: 45F9
Pump jet: 40
Starter: 150/85F9

For comparison, the jetting table listed in a post here, for a 2.0 motor, in parentheses is for a 1.9 H/C motor):
Venturi: 32 (30)
Main: 128 (115)
Air: 190 (190)
Emulsion tube: F16 (F11)
Idle jets: 55F8 (45F9)
Cam: 284 What does this number mean? (Std.)

I wish I could make tables in these posts.

I'm going to call this enough progress for the day.
 

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Rebuild Kit
This what I plan to get.

Link: 40,45 DCOE Rebuild Kit

This one does not seem complicated. Any comments?
DCOE's are a fairly uncomplicated construction really. Just be anal about keeping things clean as even the tiniest bits of dirt can clog up a metering hole or something and be especially careful with the floats as it's easy to puncture them or bend something

Air Filters
These are what I'm looking at.

Link:DCOE 40 42 45 48 K&N Air Filter Kit

These are a bit pricy. I think I saw them for about half that price on another site. I saw the little sock-style air filters but I don't think that's what we'll need.
I've always used K&N (on the street), yes they're a bit pricey but it's a one time investment as you just pop them off, clean them and reassemble and if you take care of they'll last for years in a street car, in a limited mileage race car they'll probably outlive the rest of the car

Gaskets and Thermal Isolation
This is what I have found. Seems they don't sell maple wood thermal isolators. ;)

Link: DCOE SOFT MOUNT KIT
Those are a bit fiddly and it's easy for the o-rings to pop out when you mount them and cause a vacuum leak but once in place they work well

Tools
I used to have these when I had a dual SU carbureted Volvo.

Link: Carburetor Synchronizer

Comments? I know there are cheaper Bug units, and I've seen a very clever home-built manometer.
Never used one personally, I synchronize my carbs by pulling off one spark lead at the time and listening for the drop in the revs. It's a "nice to have" item if you ask me

Other
Alan just got back from Monterey and got to talk to an Opel GT guy who had dual DCOEs. He highly recommends bracing everything. That's a lot of cantilevered mass hanging off the side of the motor. Vacuum leaks, if not actually breaking something, would be expected without doing this. The recommendation was:

1. Make a bracket out of sheet steel that will connect the carbs, at the horns together so they act more like one single carb as far as vibration goes.
2. Extend a support to the motor mount to stabilize them.

Comments?
It's def worth considering as DCOE's tend to move about a bit, I've thought about it myself a couple of times but never got around to it. The soft mounts for the Opel isn't too bad but the ones on my Alfa are horrible for this.

I'm not sure about the support to the motor mount though as I would have thought that would negate the purpose of the soft mounts in the first place .... at the very least I would have put some rubber mounts on the ends
 

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Linkage
Our carbs came with the linkage that connects them to each other, but we need the cable kit to connect them up with the throttle. Will this work?

Link: UNIVERSAL CABLE KIT
These people are excellent source of throttle linkages: Dellorto and weber carburettors online
Also these: r.d. enterprises ltd. Home Page



Jets
I'm sure I'll need one of these kits.

Link: Performance Main and Air Jet Kits
Try these as well: Weber Carburettor Specialist, Weber Authorised Dealer, Fastroadcars, Weber Carbs, Fuel Accessories, Fastroadcars



Gaskets and Thermal Isolation
This is what I have found. Seems they don't sell maple wood thermal isolators. ;)

Link: DCOE SOFT MOUNT KIT
I prefer this mount kit: Soft mount kit for Weber 40, 42, 45 DCOE's | eBay


You will also need a heat shield: Heat shield for Weber 40, 42, 45 DCOE's | eBay
 

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This is going to be a sweet thread. I am curious to see what your final carb setup is; jetting and all.
 

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Hi ya Mike,
the short time I had DCOEs on the wagon I
used r.d.enterprises for all things carbureted.
I used a Locar cable from Tognotti's to connect
my foot to the carbs.
I've got a carb syncronizer, light weight, if
we don't cross paths can mail it easily enough.
Check your email, I've got a couple questions
about evil genius.
C-ya,
Don
 

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Looking back on old records....
here's how the wagon's 40's were set up:

machined the chokes to 36mm.
idle jets: 55
mains: 145
emul tube: F2
air correction: 210

Keep looking for the thread on bracing. I
remember there was a pretty good one to
hold these things in place.
 

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Dennis Gardner had a great stabilizer option he described to me once. He said he made a bracket that connected from the engine mount to the carbs. Sounded great.
 

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Discussion Starter #10
Thanks all.

Those links are very useful. One even had prices about half of what is typical, or at least I thought so, until I realized the prices were not in dollars. The Internet sure has shrunk the world. ;)

The heat shield idea is interesting. I had wondered if one would be needed.

I'll be heading over to Tognottis soon, on a loop through Sacto to pick up Lexan for our windows and a tool dolly at Harbor Freight, and if I can find a cheap one, a power blaster. I think that may be the easiest was to thoroughly clean the carburetor body and other aluminum parts. I'll probably stop by EGR on the way back.

I searched and can't find anything here about a DCOE stabilizer or bracket. I know these carbs use soft mounts but I figure that is because otherwise they'd fail completely. I don't think they wanted to the carbs to be able to wiggle.
 

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The heat shield idea is interesting. I had wondered if one would be needed.
It's a real good idea. I made my own from .040" aluminum and covered them in aluminized fiberglass with a self adhesive backing. Used stainless steel studs for standoffs to maintain an air gap. Anything to keep the exhaust from heating up the intake side of things!

All sizes | 006 | Flickr - Photo Sharing!

All sizes | 008 | Flickr - Photo Sharing!

All sizes | 016 | Flickr - Photo Sharing!
 

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Those look great. Much better than the ebay ones.

I've got some carb cleaner. Gave up on the soda blasting idea. No room here for more stuff and even a Harbor Freight set up would cost more than I wanted to spend.
Thanks. BTW, if you go this route I have plenty of 6 mm all metal locknuts. Used 4 of them, had to buy 50! Nylock nuts tend to melt and loosen at 250 degrees or so.
 

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Some more DSD ideas for . . .

. . . carb/manifold support, linkage and heat-shield.

Weber strongly advises some type of carb/manifold support for both SSD and DSD 4-cylinder installations to help prevent leaks due to vibration, something like this . . .



. . . alternatively you could mount the support from the CIH engine pan-rail similar to my Kadett's "sprint" installation . . .



Linkage for synchronizing the dual SD carbs may be implemented either by two adjustable threaded ball links on a common throttle shaft, something like this . . .



. . . or by using the special paired, in-between, adjustable sync lever - #45048-005 - offered with either a ball-lever - #45041-009 or cable-lever - #45048-007 - connection, similar to my SSD linkage fabrication from Manta/Ascona parts to use a '75 FI throttle cable, something like this . . .



As our CIH engines use a non-crossflow - intake and exhaust on the same side - head, it becomes rather imperative that one use some sort of heat-shield with with SSD/DSD installations to prevent fuel-bowl overheating, as already amply demonstrated by Bob's awesome fabrications.

I'd venture to guess that most of us are nowhere close to Bob's fabrication skills, so let me suggest some alternatives that most of us could fabricate. I was primarily concerned with the heat generated by the center two exhaust ports when I fabricated the heat-shields for my Kadett's 'sprint' engine using the cast-iron 'sprint' manifold . . .



. . . or the heat-shield I fabricated for one of my GT's Dell'Orto DHLA48-fed 2.2 SSD engine with header exhaust . . .



I'm a strong 'CIH engine exhaust heat-shield' devotee, BTW. Hope these give some more 'food for thought'!
 
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It's a real good idea. I made my own from .040" aluminum and covered them in aluminized fiberglass with a self adhesive backing. Used stainless steel studs for standoffs to maintain an air gap. Anything to keep the exhaust from heating up the intake side of things!

All sizes | 006 | Flickr - Photo Sharing!

All sizes | 008 | Flickr - Photo Sharing!

All sizes | 016 | Flickr - Photo Sharing!
What about power/ceramic coating the heat-shields from ebay? wouldn't that be a simple solution to help with the heat as well?
 

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rmelchiori - thanks fo rthe link. There is a log of good information there, and parts.

I also saw the 'eBay" heat shields there. What I think is odd about them is that they mount to the bottom of the bowl, which seems to me like a good way to get heat INTO the bowl.

I'll see if I can make a couple of Bob's heat shields.

I really appreciate the pics of the braces for the carburetors. We will definitely be doing something about this. I'm glad we have 5 motors laying around, three on engine stands, that we can use to test fitments.

I'm going to go ahead and order rebuild kits, a balancing tool, and the DCOE book and basically everything I know for sure we will need. I'll hold off on jets, chokes, and the throttle cable until later. I have two of the Haynes books on Weber carbs and as helpful as it has been it doesn't go into the operating principle the way the Holly 6100 book.

I also still digging though the posts here to learn more.
 

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You can also make a manometer. No need to mess around with mercury.......:no:
Google
 

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A few more suggestions . . .

rmelchiori - thanks fo rthe link. There is a log of good information there, and parts.

I also saw the 'eBay" heat shields there. What I think is odd about them is that they mount to the bottom of the bowl, which seems to me like a good way to get heat INTO the bowl.

I'll see if I can make a couple of Bob's heat shields.

I really appreciate the pics of the braces for the carburetors. We will definitely be doing something about this. I'm glad we have 5 motors laying around, three on engine stands, that we can use to test fitments.

I'm going to go ahead and order rebuild kits, a balancing tool, and the DCOE book and basically everything I know for sure we will need. I'll hold off on jets, chokes, and the throttle cable until later. I have two of the Haynes books on Weber carbs and, as helpful as it has been, it doesn't go into the operating principle the way the Holly 6100 book does.

I also still digging though the posts here to learn more.
. . . for you, while I'm thinking about them. First, and to answer your quoted question above, I have a few really old Weber DCOE manuals - even a couple in Italian, no less - but I don't remember where I got these DCOE THEOPS illustrations, just that it was a very long time ago.

Believe these will answer your question, though . . . main thing to note is that mixing blue (air) and yellow (fuel) combine to make/equal green (air/fuel mixture)!

DCOE/M idle and idle/transition phases:

_________


DCOE/M accelerator phase:



DCOE/M wide-open phase:

__


Hope that answers your question . . . HTH!
 

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And also . . .

. . . onto a few more items worth mentioning. If replacing the head-gasket, don't remember if you've removed the head for your project build, remember about the extra head-gasket cooling holes near the 2/3 exhaust ports . . .



. . . remember, too, that these carbs require an e-pump that is regulated to no more than 3.5psig . :p . fuel pressure, this is one I can recommend . . .



. . . and finally, an earlier thread mentioned some problems with the grooved anti-vibration dampers between the carb and the intake. Misab SD dampers are the thinnest I know of, basically just a thin metal 'gasket' with a rubber 'O'-ring molded in, something like this . . .



. . . again, HTH!
 
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