rb25det correct air fuel gauge reading

[quikdime]

I have a basically stock stock rb25det in my 240sx. It has a front mount intercooler,a test pipe,Nismo fpr (set at 37psi) and 3 inch exhaust. It runs fine. I want to get a baseline on air fuel mixture because I want to install a boost contoller. I installed a Uego AEM air/fuel gauge today. I am not sure if the car is running rich or lean. How do I read the gauge correctly before I turn up the boost? I want to make sure I dont blow up the motor. Thanks in advance

[Carl H]

14.7:1 is ideal...lol.

but seriously its dependent on load...under full boost 10.5-12:1 depending on tune is considered safe...nissan stock ecus generally run very rich with afrs in the high 10's under boost.

[240z4u]

14.7:1 is ideal...lol.

Man, I remember that idiot. What a tool LOL.

I have tuned my a/fs in the past to about 11.7 on pump gas with very good results.

Just wanted to reassure you carl was right on!

Evan

[quikdime]

Thanks for your help. I installed a profec b boost controller and took a spin. At low boost setting (7 psi) the reading is around 10.5. Same for the high boost setting (13 psi) is about the same.