what is a safe number, what is to lean, what is to rich, mine is set at 12.0 to 12.4 with a average of 12.2 thanks

 

Part throttle, idle, or full throttle? No one can give you any information without knowing what modifications you have done. Ideally you'll need to get on a dyno. Stoich is 14.7:1 though.

 

Since you can't really control A/F ratio in closed loop, you must be asking about WOT conditions. Typically, you look for something in the range of 12.8 - 13.2:1 to produce peak HP/torque. But there is no "one size fits all" answer. That's the purpose of "tuning" - experimenting with various combinations of ignition timing, A/F ratio, coolant temp, etc, to find the specific combination of the variables that produces the performance you want over the range of RPM that the engine will be used.

 

yes it has been dynoed lt4 hot cam, 1.6 rockers, jet hot long tubes, 286 to the wheels on a mustang dyno,what I was wanted to know is lower the number is it rich or lean, that why the number was from 12.0 to 12.4 so am I running on the rich side or lean side. thanks

 

You're running pretty rich.

 

The A/F ratio is the ratio of air mass to fuel mass. The larger the number, the more air there is, in relation to the fuel. That's lean. The lower the number, the less air there is in relation to the fuel. That's rich.

You said:
How was it set? Did someone tweek the PE tables? Did they tell you that's what they set if for? Who tuned it for the cam?

The stock LT1 tuning usually nets you a "too rich" 11.7:1 A/F ratio in PE mode. Knowledgable tuners can pick up 10-15 HP simply by leaning the PE mode target A/F ratio closer to 13.0:1 (+/-).

 

Depends upon the usage also. I currently run 12.2 AFR just because I am being cautious with such a high CR. If you have ever looked at an AFR chart vs torque, you will see that a little rich will not take much away but is safe.

 

In comparison, my cc503 1.6rr setup made 325hp 321tq on a Dynajet with a 14.77 AFR.

 

Im going to tune mine in the 12.5-13 range to start

 

I have a descreened & ported mac flow air sencer how much will it change the ratio the tuner would not tune it with it on the car put a stock one on to tune it thanks for the responds

 

No one can tell you how much a hacked MAF sensor will screw up the flow calibration. That's why tuners don't like to work with them. There is not much, if anything, to be gained with what you did with the MAF sensor. Why not just put the stock one back in and run it the way the tuner intended.

 

I didn't hack anything I just happen to have one the stock one is on the car just wanted to know if anybody tried one I did want to be the first, thanks anyway sometime you learn by other persons mistakes

 

I didn't say you hacked it. Not trying to start an argument - just trying to help.