From what I gather on the net, a 12 volt Stewart Warner gauge has a resistance of 240 to 30 ohms. Many of the aftermarket sending units match this resistance range. However, the 6 volt gauges are supposed to run from 90 to 0 ohms.
A way to get around this might be to install a potentiometer inline and with the 12v sending unit fuel arm to full, adjust the potentiometer to read full. Or you can do it the other way around to match with "empty", which, in my experience, is more important/critical.
A google search shows plenty of 90-0 ohm sending units available from Summit racing. You will want to use either an adapter ring to go from the ford 6 bolt ring to the SW 5 bolt ring, or else get a 5 bolt ring if you are making new tanks.
|