I am sorry but the long and short sender both use the same wire guage and are the same resistivity. The 280mm sender cannot have an advantage.
Charles, hello.
Either I'm missing something in the way you're suggesting that long sender versus short sender make no difference in true tank fuel level, then please explain what I'm missing.
I've done a quick sketch in AutoCAD to show what I'm thinking.
To take it to the extreme, I also represented a 100mm long VDO sender.
Now less assume that each of these are calibrated to allow the dash gauge to read 0% fuel at the bottom of the sender.
You can clearly see that at 0% on the 280mm you will be closer to the bottom of the tank and hence there will be less fuel in the tank at that reading.
The extreme would be the 100mm and when it's at the bottom of its range, it too would give the gauge a reading of 0%. Again you can see in that case that the 100mm at the bottom of its useful range, you would still have well over half a tank of fuel.
So you suggestion that it's not an advantage to use the 280mm sender, doesn't make sense to me, please explain.
My sketch does assume that all three senders are in fact working the way they are supposed to and for the given application would give out the correct resistance for any travel within their useful range.
