What on earth this gas tank? Early model top with ??? bottom?

[MaxBell]

I bought this gas tank, and when it arrived, this is what I got. What the hell is this?? It's an early model from the single hole, but it's missing the second side of the tank! Look how it doesn't drop down on the passenger side!

WHAT IS THIS!?

[roguetoaster]

It's the pre whatever month of '83 fuel tank.

I just don't know what they installed in the void they created, but I recall seeing some type of mounting bosses on one of our old race cars.

[E30SPDFRK]

9/83 is the cutoff I believe, there is nothing extra down there in the extra space. At least not on my 5/83 318i

[Jaxx_]

Yep, I have the same gas tank in my 5/83 production 1984

[kronus]

yup, tossed the one that came with my 6/83 and put in a late model tank.