I am going to be street tuning my car tomorrow morning using aem wideband and safc2. I will be on pump gas, stock turbo, 680cc injectors, fuel pump, 272's...... My ? was what is the ideal a/f ratio i should be tuning for using the wideband? when is it starting to hit the dangerous area of too lean? please help! thanks.

 

What octane pump gas are you running? My car is around 11.3 afr on CA 91 octane.

Thanks,
Tom

 

i will be running on 93 octane.....i was thinking to stay around 11.5 or a little higher but i dont know if dipping into the 12's will be running too lean....

 

This is a subjective question. There are many factors that you have to nail down before you can say 11.2, or 11.8, or 10.6, etc.... I personally am running an atp3071R that is kinda laggy up to 1 bar. From 0 to 8 psi, I usually run 12.6 to 12.8 to help the spool up. Once I hit 8 psi, I then start to richen it back up to 12.0 at 15 psi. From 15 psi up to my target boost level, which for now is 23 psi, I taper down to an end result of 11.3

With this being said, it is very important to watch your egt's and knock counts. If you experience knock, you may need to back out of the timing a bit. If you don't have control of timing, then you should richen it up slightly to counteract the knock.

This post could go on and on, but this is the very basic target for my ride. i hope this helps!

 

BTW I too am running 93 octane, and not that 91 pee pee gas!

 

You're going to be pulling over 20% fuel, which will radically advance timing. I'd get a scan tool so that you can see how much timing is being advanced and also whether you are getting timing retard from knock -- which could be caused by being too lean or too advanced, or a combination of the two. You'll be much faster with a richer AFR and good timing than you will be with a leaner AFR and overly advanced (i.e., overly retarded when it knocks) timing.

 

thanks a lot for all of your replies...... i will watch the knock counts carefully and i will look into the scan tool.