quote:Originally posted by Corey Price:
So guys, if you run IDF's and air cleaners, are you going to have a fire? I'm sure it has to do partly with the cam selection. I read an old post from Dave (Whiplash) that said he took his air cleaners off after having two air cleaner fires. Not having air cleaners seems like it would shorten the engine life.
Corey
I know you're capable of researching the internet ... and that's what I encourage you to do.
If a person's only exposure to the world of Weber carburetors is the IDA, then it has only scratched the surface, and not the best surface either. Weber carburetion is popular world wide on smaller engines, both with plenums and with individual runners. The american V8 muscle car crowd are the only hobbyists that adore the IDA carburetors, its actuallly a small market for Weber. As they were originally designed they are a racing carburetor for a motor that is either accelerating at WFO or braking. I'm sure there are guys who can modify them to work better ... if that's where your head is at.
The IDF's are used in many more applications than the IDAs; like the DCOE, the IDF is a very popular twin throat racing & high performance carburetor. It has been used as oem equipment in a few limited production vehicles, including a Ford Escort (the European Ford Escort RS2000 Group 1 cars). And it is accepted by very many sports car hobbyists as an acceptible replacement for various Delorto and Solex carburetors. It is also sold by Pegasus Racing due to the demand for the carburetor. IDF Webers are offered in 40, 44 and 48 mm bore sizes. The main, idle, air correction and accelerator pump jets, the emulsion tubes and venturis, are interchangeable. It has a float design that makes it very popular for off-road applications, a vacuum advance port, and four progression holes for smooth light-accelerator response. The differences between the IDA and the IDF, like the additional transfer circuit, add up to make a big difference in performance. You can bet the IDF would not have been selected for oem applications if it's calibration were as easily upset as the calibration of the IDA is reported to be.
Individual runner carburetion has been used on many production automobiles and motorcycles ... AND Every Single Cylinder Internal Combustion Engine Ever Made ... think lawn mowers, leaf blowers, chain saws, generators, etc. They don't have problems with altitude and fires. So continue your search on the internet, you'll find the answers you seek. I'll tell you what I know. Inglese uses wide lobe separation (115 degrees) for the cams he sells for IR. So one can assume from that bit of info that overlap is the source for some of the problems with IR systems. I have helped a couple of guys install IR weber systems in my past; one was an IDF system on a Ford Fairlane (Windsor) V8 ... the owner was happy with the results. Another guy chose an IDA system for his SBC, he was unhappy with the results, so he eventually sold off the IDA system, purchased an IDF system, and has been using it for over 20 years.
Pictured below is an IDF system fitting under the engine screen of a Pantera
-G
