if you still have this problem. check your thermostat. If it is running hot then it is stuck closed or it dosnt open as much as it should. Mine never got past the blue cold square and i found out that it was stuck open.
E30 4sp Auto trans for early model 320i or 325i
only done 145,000 kms $500. Heavy duty forward clutch pack installed. Also ready for torque converter install. also standard springs and a/c compressor and radiator for sale