I own an 83 280zx turbo and the timing does not seem to advance enough. When you set the timing to the correct position the engine stumbles above 2250. If you advance the timing the top end runs great but it stumbles at low end. I have changed the distributer and found that it is advanceng but not enough. It also tends to run rich. Can someone please help.

You can download the factory service manual here:

http://www.xenons130.com/reference.html

I have never worked on the turbo engine, but I remember from the FSM that the distributor is totally different than the NA cars.

SBlake01 might be able to help you more.

Had a Similar Problem some years ago with a 1983 280ZX Turbo ( L28ET ) - Car would NOT go faster than 35 mph or so IN ANY GEAR. . . . . . .

Take it out of gear and the engine would rev to any speed I wanted . . . . .

Found out that the EGR Tube was plugged AND the Speed Sensor Circuitry

( Think Cruise Control underneath the passenger seat ) had some corroded connections - fixed both of those and problem solved. Even though the Cruise Control was "OFF" - it still stays in the circuit. . . . . .