Target AFR for NA 13b
 

Looking to see what Target Air Fuel ratio people are using for a naturally aspirated 13b.

I've had success with quantifiable results on an engine dyno using 13.2 afrs and 24-25 degrees of timing at torque peak. You can feed a bit more timing in before and after.

Keep in mind that any bit of ethanol in the fuel, even pump gas which is e1 to e10 will shift the stochiometric down.

12.9 to 13.3 is generally ideal for non turbo engines and 25 to 31 degrees timing at wide open throttle . A dyno is needed to measure exactly what the engine likes.