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Ferrari, Lamborghini, Cobra, GT-40, Webers, Webers, Webers. My dream Pantera engine has always included four Webers.
I picked up a Hall manifold a while back and have been looking into Webers to fill it out. I found a guy with two Chevy circle track set-ups, and while he was unwilling to part with them, we got to talking about tuning and such and he made some interesting points.
On a road course race track the elevation changes no more than a few dozen feet. You can tune a Weber set up to run optimum for each cylinder and taylor that tuning to each track.
I live in Colorado at an elevation of around 4000 ft. The canyons of the Rocky Mountains are just 25 miles away. Driving around here, the elevation can change by 10 thousand feet in a hour or so.
Is a Weber set up even sane or reasonable for me? My friend suggested that setting it up for this altitude and then running to Las Vegas might result in a lean-out condition that could burn up an engine!
All this has me thinking. Can any of you that have run Webers on your Pantera give me your insight and experiences?
I may have a Weber manifold for sale soon!
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the webers are no worse or no better than any carburetor in dealing with altitude changes.

most folks I know who have run webers eventually go back to a single 4 barrell set-up for reliability. the webers look cool & run great when properly set-up. one problem is the weber carburetor our Pantera family has chosen to run, the 48 IDA. The 48 IDA is a racing carburetor with a idle circuit & a main metering circuit, but no intermediate metering circuit. The 48 IDF is a street carburetor that has an intermediate metering circuit, but the throttle bores have different spacing, so they don't bolt onto the same manifold as the 48 IDA.

perhaps an individual runner fuel injection system with barometric compensation would be a good way to employ that Hall manifold & fulfill your dream of 8 "webers". Pantera Performance Center specializes in that set up. (Since they're in Colorado, that may explain why!)

I would agree with the Pantera Performance fuel injection setup.

I did ask my racing partner to comment on this since he has some experience with Webers.

"The rule is that when running on higher elevations, make the mixture leaner by either making the air jets bigger or running a smaller
main(fuel) jet. What I do is have two sets of bleeder assemblys (holds both jet main/air & main/fuel) and swap. And, for every change in main (fuel is equivalent to 3 changes in 3 main/air)."
IMO, if you expect to routinely encounter altitude changes of 10kft, you need to be fuel injected, if you want optimal performance. Whether that is an IR set up or a 4-barrel conversion is not as material as the ability to actively sense manifold absolute pressure (and other inputs as afforded/required by modern ECUs) and alter the fuel air mixture accordingly. Depending upon your ECU and desires, you can realize a variety of other benefits from FI as well.
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