Since my car has downdraft Webers and since the owner of my local Z shop has retired, I am faced with trying to balance my carbs after I diddled with the linkage. I know there are flow meters and adapters available for the Webers, but it occurred to me that there might be a way to locally fabricate something.

My son and I used to balance the four carbs on his Suzuki using manometers, but he had one carb per cylinder and no balance tube to deal with. I realized that pressure measurements were a poor substitute for what we really needed, an air mass sensor ahead of the carbs. Then it occurred to me that cheap air mass sensors should be available from the salvage yards. Since we are looking for balance rather than absolute measurement, circuitry should be an absolute minimum and calibration not a problem.

Has anyone tried this?

Any suggestions on which air mass sensor would be the best candidate for the experiment?

Water in hose Manometer is best. Your physical senses are surprisingly precise too. I have used my fingers to "feel" the air flow to balance then check with a flow meter as well as the "sound" of the air flow. It was pretty close.

I made a digital manometer for a flow bench using this:

USB Experiment Interface Board | Velleman Kit K8055N | Quasar

and a Motorola pressure sensor MPX4100a http://linuxfocus.berlios.de/common/src/article284/MPX4100A.pdf

You can probably just use a voltmeter, +5V supply, a piece of pipe and the mpx4100a to make a tool

I have weber DVG carbs on my 260z. Not a bad idea making your own meter and I would support you making your own out of sheer coolness. I dont have that kind of time though and found a guy on ebay with a pair of syncrometers he used on a porsche. I picked up 2 meters for 30 bucks, then bought the weber adapters for another 30. technically you only need one meter but it was easier to do with a matched pair. The meters are pretty generic too so with different adapters you can use them on almost anything, they fit round mouthed carbs without adapters. I might be spouting BS here but I have only needed to balance the carbs after tuning them so its not very often i even need to deal with the syncrometers

Yes, a friend of mine is developing this right now for use in his own shop. Original Customs in Sonoma CA. Like Original Cusoms on Facebook and ask him about it...