SAFC setting difference in low (1000ft.) and high (5000ft) Elev.???

[gsxtacy]

I am really curious about this aspect of tuning. I know that at lower altitudes the air is more dense...so at higher altitudes the air is less dense......How does density affect air/fuel ratios??

Should I richen the lower in altitude I go or lean out?

Thanks

GSXTACY

 

[2-0turbo]

You shouldn't need to do anything. The ECU uses frequency (Karman), barometric and temperature sensors to compute the mass of air entering your engine. The SAFC is only monkeying with the frequency. As your altitude increases, the barometric sensor will report a drop in ambient pressure, which will all figure into your mass air calc. You shouldn't have to touch a thing. Welcome to EFI. Carbueretors are different.