How many different sizes do these come in? Are these worth running in single applications? Are they pretty finicky to tuneor can any idiot with a hammer tune one? I thought I remember someone on here running a pair of the pinto carbs on a Ford six. -Jesse
Here's a Webber adapted to a flathead. This was done by Russ Daly from Newport, RI. He's a pretty clever guy.
I run Weber 40idf carbs on my Porsche. Pretty simple to tune. Helps to have a Unisyn to balance them. There are several sizes, 34, 40, 44, 48mm. I've seen 52mm that I think are custom made.
Because of their replacable venturi's webers can come in any size you need. They are arguably the most tunable carbs on the planet. As long as you have a flowmeter(a cheapie will work) tuning and syncronizing is fairly easy. -Jeff
Chris at prolinefuel.com sells Webers and is quite good at telling you a few tricks on tuning these for any application. You can contact him at the above e-mail and ask questions. I know that he is building some intakes and setting them up on various 6 cyl and having good luck with them.
Lamborghini Muira's back in the 70's used four of the 40mm IDA's on them and they were impossible to synchronize without a Uni-Syn.The Espada's used the same engine but it was mounted in front and used six two throat Webers(not sure of the model)and for some reason was easier to sync. The 40's had a tendency to run rich and fill the enormous air filter with gasoline and at the first backfire(which these engines loved to perform if not properly warmed up)would result in the incineration of the rear of the car. I worked at a dealership that sold them and I think of the five Muiras we sold,four of them burned.
As far as running a "Stand alone" Weber..., I see no problems other than having the right size venturie and jets. To determine the venturie and jet size you need to tell us what model of Weber you plan on running as well as size of your engine and what other modifications were done to it. I've tuned many cars with multiple Webers and SU's, you definitely will need a sync meter for multi carb applications and a highly recommended Colourtune for mixture settings. Regulate the fuel pressures at 3.25 lbs. (no more) otherwise they will flood over and cause your air filter to ignite when it backfires!!! I've never had troubles with Lamborghini's with Webers after I tuned the carbs and replaced the fuel regulator with one that has an accurate gauge!! Mark
I was thinking a 40 IDA on a 235 Chev with the clifford 270* cam, fenton manifolds, and a slightly shaved head. If I can find another SU I would run 3 of them, I got two 1 1/2" venturi side floats off a sixties Jag. I think the single 40 would be far better on a mild stovebolt. -Jesse
3 SU's would be awesome for the 6..., plus the venturie size should work for the cubes. About the same size as a Jag engine, minus the overhead cam and a little quench. Single 40 Weber would be the simplest of the setups, but not as impressive looking! Stack three of them on that engine and that'll get some "WOWs"! Do you have the Weber already? If so you can call "Fast Freddy's" and tell them your engine combo and they would be able to calculate the proper size venturie, air meter and jets for you! I've gotten pretty good messing around with Multi-carb combinations, but you'll have to call around for a Single carb components to work with your engine!
After years of playing with Webers, I bought my first Holley. Took me forever to get it dialed in right. I guess is is just what you are used to... On a straight 6 I would use 3 sidedraft Webers ( or Dellorto's ), if there is no fenderwell clearance problem. I would stay away from the SU's, I am not a fan of those. But again, it is probably just what you are used too...
OK... Webers I know a little about... sold them for like 10 years. As far as performance downdrafts, there are 3 major series of the top of my head dcnf, idf and ida. These are non-progressive. Each is available in several sizes. The 52mm that someone mentioned were an aftermarket item. Webers are sized by the throttle plate rather than the choke (venturi). The weber shown on the flat head and most likey the one someone mentioned running on a Porsche (assuming it's a flat-6) would be a 40ida3c. 3c meaning that it's a 3 barrel as most webers are 2 bbls.
So what are the differences between the 3 different models? I was thinking about the 40's that Clifford sells but may go out andfind a couple of pintos and stealing their carbs, any specific models to look for? -Jesse
OK the Pinto carbs aka Holley/Webers etc. are a different design completely. They're a progressive... like a 4 bbl with a primary and secondary. The DCNFs are pretty small physically with a small retangular base plate and the float bowl on one side. IDFs and IDAs are fairly similar. The major difference is that IDF have a diagphram style accelerator pump where as the IDA has a pluger style. The IDA is physically larger than an IDF. Also IDAs usually have nickle plated air horns on them. The both have separate base plates for each bbl. Also the IDF has a few more transfer ports than an IDA so it transitions from idle to main circuit a little smoother. IDF is available up to 44mm whereas the the IDA goes up to 48mm from Weber and modified up to 55mm. Also... I know that IDAs have separte air and fuel jets for the idle circuit and I think that the IDF uses more common Weber method of using one jet to control both, If this is the case then the idle gets would be sized something like f9 .085 where f9 would be the size of the air control and .085 would be the size of the fuel control. All of these Webers meter fuel almost like a fuel injection would. I would guess that the 40s that clifford sells would be an IDF as that's the most common. IDAs are generally considered to be the top of the food chain. The strength of Webers is also their weakness. They have more sized parts than any other carbs. Once you get the jetting figured out, they'll run great. They'll only need occasional syncing after than.
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