Two things will wake that car up.
Get a chip for the ECU, they are around $50 on E-Bay.
Get a gear ratio change for the differential.
You can use any of the following with a better ratio.
The ratio is on a tag on the aft face of the differential.
The OE 1984 eta was a 2.79 to 1.
I recommend 3.25 to 3.73 to 1.
You can use a differential from any of the following cars
e30-6, e28, e24, z3
Here is a link for reference as to the possibles.
http://www.bmwe30.net/cgi-bin/datacgi/data...0025&Section=03
Later,
