Altitude base timing

[falcon8r]

Hi all, I live at about 3000 ft elevation. The factory manual indicates a different base timing above 2300 ft. What are the advance numbers that work? Would the knock sensor compensate anyway? I know any timing retard is bad so there must be a good point . I too know these turbo cars are all kinda different within each other but.... Tres...

 

[DSM1G90]

In the olden days, you'd adjust the timing and carburetion per what altitude you were in. If you bought a car in LA and move it up to Denver, you would be putting in smaller jets and advancing the timing 6 degrees above sea level settings - one degree per 1000 feet.

Nowdays, the ECU takes care of all of that. It communicates with the OX sensor which is sensing oxygen levels - either lean or rich oxygen levels.

..and the ECU tells the injectors how much fuel to be sprayed in on how much oxygen is sensed.

I live at 2800 ft and I still maintain the *5 BTDC timing requirements. In fact, my car loves it when I go into cities with higher altitudes..runs a bit better and I get increased mileage..

-DSM

 

[steve]

The base timing (what you set the CAS to with the timing adjust pin grounded) doesn't change but the timing when you disconnect the timing adjust mode does.
At sea level it's about 8-10* BTDC and you'll have something different at altitude.

 

[falcon8r]

The base timing (what you set the CAS to with the timing adjust pin grounded) doesn't change but the timing when you disconnect the timing adjust mode does.
At sea level it's about 8-10* BTDC and you'll have something different at altitude.

I guess I mis-read the page in the manual( 8-175, vol II). It just meant what you said. I thought this weird too as that would throw off the injector timing also. Thanks.. Tres....