What is IDE and DCOE and any other carb acronyms ( or is it models ? )

Hell I don't know... that's why I'm asking.

 

Youre right David, the letters are models of carbs. The DCO series carbs are sidedrafts (lay on top of the engine). The DCO is essentially the same as a DCOE, only the DCOE has a choke. The IDAs are down drafts (straight down), although I dont know much about these. Those are the two more common used Weber carbs on our cars, but they also used DGV carbs, which are down drafts as well. A good Weber website will show you different carbs and models. I hope that clears some of it up!

~T.J.

 

Dave,

The IDA's are a race carb developed by weber(no provisions for choke) , the IDF is identical with the exception of a butterfly choke system. Great carbs but most people don't bother to tune them right, they just grab it outa the box and slap it on, then they complain about the performance. being that the IDA/IDF's use a very short manifold length they tend to have better acceleration than the DCO's or the Solex/Mikuni side drafts, thier mani goes up and over the top of the engine making for a very long intake runner, good for torque, but lousy on acceleration . Biggest problem for most people is the emulsion tube setup on the IDA/IDF "very tricky grassahopper" just check out RB's data for the emulsion tubes, I tried throwing in different ones on my last NA race engine and it just drove me nuts so I used theirs(sizing) and it ran great.

Ken

 

I thought torque was essential for accereration?

 

Torque is essential for hauling, for instance if you have a 4000 lb car, then you would need more torque. If you have a 2000 lb car, (us) you don't need near as much.

 

can you put a choke from an "IDF" into an "IDA"?.....

my new rex has the weber 48 IDA, but i live in canada, and although im not driving it in the winter, the spring and fall seasons fall below 0 celcius....so i NEED some sort of choke...(or maybe a block heater)?

anyone have any insight into this?

thanks, nick

 

The IDA and IDF are far from identical.

 

They are not identical, but the biggest differences for our purposes are the fact that one has a choke, and one doesn't. either flows enough to run a seven in any of its porting varieties, and there are many locations that will bore out the body, so that its 51 mm bore vice 48 (for the IDA only) they are easily modified to accept the oil feed and they offer a compact neat appearance.

about the torque vs HP flame war thats about to start Yes, but, is my answers

yes torque is very important but side draft manifolds that I refer to are great for daily driver in traffic, lots of (comparativly speaking) low end, but its acceleration is seriously lagging behind the shorter manifold for the downdrafts. they basically suck at upper RPM's and have a lot of problems with fuel puddling due to all of the extreme angles put into the manifold. the downdraft weber with its short manifold puts a rotaries power band right where it needs to be for spirited driving including the ability to rev, and sustain power well past 9k on a bridge or perry, or as low as 5~6 K for a street port. often times your limiting factor becomes the ignition when dealing with the IDA, or IDF. while important for any engine the differnece becomes immensly apparent with a weber downdraft as the horsepower potential goes through the roof with a good ignition system

anyways go with what ya know, and if you prefer the slightly less free reving sidedraft manifold go for it, if you regulary pull a camper, or have put on some extra "grins and laughs" lbs in the past couple of years then use the side draft.

thank god for my mountain bike to keep me sane, and below 190lbs!

cheers

 

Kenn Chan great info!! So than for a racing application an IDA is better than a DCO. I've got to find someone who whats to trade a 48 IDA for a 48 DCO.

 

good luck finding one.

 

very well written.

 

Although you don't have to have the long over the top intake runners, you can get a manifold so the dcoe sits next to the engine....

I have a question: when some one has "Twin 48IDF Webbers" for like a 2 4cyl car, is it 2 idf's or two smaller carbs which make up what would be equal to 48?

 

I got one on ebay right now. Not interested in a trade though unless the trade is lotsa cash. And it has the shortest intake manifold you can get for an IDA.

 

Who makes DCO/Mikuni/Solex manifolds that sit right next to the engine? All I ever find in my searches are the over the top variety.

Still deciding which I want, but it would be good to have a manufacturer to compare with.

 

Mazdatrix, Rotary reliability and racing, and
Racing beat.

 

yes, kudos to kenn chan on the writeup. you've enlightened me on a few points.

thanks
1

 

Okay..
Heres the deal on weber carbs and what all the letters mean... I'm quoting this from my weber carb borders book..

From P11..
WEBER FAMILY TREE

..It's not easy to organize Webers into neat families for two reasons. In the first place, Weber didnt set out to consrturct a a tight little family of carbs. He was interested in building carb that best matched the current need. As a result, there was never an overall scheme of things. Second, he named carbs in his native italian. So if your unfamiliar with words like doppo corpo or orizzontale, weber terminology can be confusing.
To further muddle the issue, weber typically created different model numbers whenever he could. He would give carbs unique names even though they differed only in jetting or some similarly undistingguishable feature. Thus, a DCN fitted to a Lamborghini was a DCNL. If fitted to a Ferrari, the same carb became a DCNF! Another twist is represented by the IDA carb. It may have either two or three throats, yet the same identification letter.
While it would be helpful to have a neat chart of Weber terms, its simply impossible. Nevertheless, as chaotic as the terms are, there are some common threads in how Weber named his models.

MODEL NUMBERS
A Weber carb is designated with a series of numbers, then letters, then sometimes, more numbers. The first set of numbers is called a prefix, the second set, a suffix. The letters in between seem to be the first letters of Italian words, but not always.
The prefix always indicates the size of the throttle plate. For example, the 40 DCNF and 40 DCOE both have 40mm throttle plates. The rule that the prefix refers to throttle bore diameter is only one of two sure-fire rules in Weber nomenclature. The other is the jet-numbering convention described later.
The letters immediately following the prefix refer in Italian, to the general type of carb. Only a few terms are consistent: DC means doppio corpo, or double-throat; V means verticale and O means orizzontale (vertical & horrizontal respectively). The I in IDA seems to mean invertito, or inverted. Yet, there are no up-draft, or inverted Webers: the IDA is a downdraft. Other even less-consistent single-letter designations are:
E - Die-Cast carb
F - Ford (or Ferrari?) application
V - carb with a power valve
A - Water-operated automatic choke

Any numbers following the letters are variations of the basic type: the 45 DCOE9 is a variation of the 45 DCOE. But, note that, to date, there are 10 known variations of the 45 DCOE9!
SO Weber carb nomenclature is chaos. To return to the IDA , there may be three, as well as two throats, and there is no choke at all.
Here is one last example of how the terminology collapses. The 40 DCO carb fitted to the early Alfa Giulietta Veloce follows the nomenclature exactly. It is a double-throat horizontal carb with 40mm throttle bores. The 40 DCOE of later Alfa use, however, is is niether die-cast nor equipped with an electric choke. In this case, the E indicates a trapezoid mounting bolt pattern instead of the rectangular one of the DCO.

JET SIZE DESIGNATION
When it comes to jet sizes, Weber is refreshingly consistent in numbering the replaceable jets. Air-correction jets, main jets and idle jets all have numbers expressing their actual flow rates in hundreths of a millimeter (0.01mm). A 115 main flows the same amount as a perfect hole 1.15mm in diameter.

EMULSION TUBE DESIGNATION
If your sizing emulsion tubes, however, there is absolutely no hope in the linking function and nomenclature. Numbers for emulsion tubes are assigned chronologically. You can be sure an F-45 emulsion tube was designed after the F-44, but thats about all.
Some idle jets have F-numbers that indicate their ability to emulsify fuel. There has been some deciphering to make order of their numbering. According to Phil Deuchene of BAP/GEON, the following chart applies....


that was from Pat Braden's Weber Carb book. Well worth the 18$ if your spending 200+ on carb & manifold...ect...

Hope this helps you choose one, i went with a DCOE..

Someone archive this, I will never write it again!