Reply to "Weber IDF's and Panteras"

The Webers-on-a-Pantera subject comes up every few years. I have adapted various Webers to several cars, including V-8s. It is not simple to get both power and decent fuel mileage. One or the other is the norm.... First- in IDAs, there are five jets, two air bleeds and a replaceable emulsion tube & venturi- per cylinder- and they all affect each other during engine operation. The last time I checked, the cheapest jet was $6 USD. It is possible to tune them at home with primitive tools. It is also possible to go broke doing so. If you have never been involved with a set you already own and are impatent to use them, find and pay an expert. He will need the entire car or at least the whole engine on a dyno stand, for perhaps a month.
Second, Weber/Italy stopped making carbs in 1985, switching to EFI. There is a Spanish subsidiary that now remakes a few models, but most are Chinese/Taiwan/Indian copies that are known to leak thru poorly done castings. Be wary of E-Bay Webers! There are ways to ID genuine carbs but it's not real easy.
Finally, genuine NOS Webers have been on the shelf for 30+ years, so all o-rings, gaskets and the ball bearings in the throttles are bone dry & have shrunken. They will likely all need a rebuilding even if they're still in the OEM bags & boxes. On a 5.7-L V-8, 48s are about the smallest Webers you should try IMHO. 50s, 52s and even larger are second-mortgage territory for most of us. I know little about the giant "Webers" built entirely in CA and used on hotrod VW sand rails, some of which use 454 Chev-sized pistons.
As for IR- EFI, the neatest rig I know of uses 48IDA carbs with dummy fuel feeds & the venturis removed, as throttle bodies for hidden EFI systems. People that can build such things are even more 'special' than good carb tuners, and more pricy. Owners who want the vintage look and modern performance don't mind paying. One GT-40 owner has had a fabricator working on his 'real' Weber/EFI system for about 5 years.