A/F ratio for Sr20

[driftking777]

i just got my 240 back to my house from chicago and i have an apexi turbo timer and it shows me the A/F ratio and i was wondering whats a good place to be sitting at...when im floored it goes to 10.0 or below...when im just cruising its at about mid 13's. is this good or bad...motor seems to be idling alittle off...anyone know why...thanks

[nissanfanatic]

Generally people tune to 11.5 to be safe. Some venture into 13s or so to make peak power. 12s should be okay for the occasional street run. 10s are pretty rich. I'm pretty sure all the stock ecus rich out under full throttle. Its a saftey thing.

[Miata Master]

yah that is like perfect 13 is the perfect ,stouchiometric level, I believe is the term. it take 13 parts air to completely burn one part fuel by weight. that extra three at full throttle helps cool so less chance of detonation.

[lucki17]

i thought stouch was 14.7:1? and also impossable to get.

[nissanfanatic]

14.7:1 is perfect, but not safe.

[mynismo]

Originally Posted by lucki17

i thought stouch was 14.7:1? and also impossable to get.

NOT FOR A TURBO! lean it out to 14.7, and it'll go kaboom

1. your gauge is inaccurate unless it has a wideband o2
2. 11.8 @ WOT

[driftking777]

my o2 reading at idle is like .85 or so...then when im gettin on it...it goes to around 1.02 or so....normal or no

[mynismo]

you have a narrowband sensor.

throw it out the window. all it tells you is if you are above or below 14.7. if you are anywhere near 14.7 your engine is around very hazardous fuel zones.





read rule no. 1 again: "1. your gauge is inaccurate unless it has a wideband o2"

[driftking777]

WOW...that was really helpful thanks for the graphs and stuff...helps alot...

[Matthias_]

i was going to offer help, but mynismo pretty much just kicked my ass in the knowledge department