Facelift e30 fuel tank and gauge

[turbolizard 38]

In the "Meet Alice" thread there is some discussion about fuel tanks and senders. I am keen to know more...

The facelift e30 tank has 2 level senders, as the tank is separated around the driveshaft - Pre facelift had a pipe connecting the 2 halves at the bottom but the facelift one does not, so uses 2 level senders to read the level and I believe syphons fuel to the pump side somehow, or maybe theres a transfer pump on that side

Yes it has a syphon type tube to equalize, where the return line enters the LHS, travels down to the bottom of the tank, along & rises up over the bridge & down into the swirl pot on the RHS.

I have a 318 facelift and the fuel reading is steady but after track driving it can be all over the place. Is this because of fuel transfer from one side to the other getting messed up by hard cornering? How do you know how much fuel is really in the tank?