Reading AFR Gauge
 

Sup guys,

So im a noob when it comes to this kind of stuff.

I bought a s5 n/a couple weeks ago and had some mods done already. One being an innovative wideband.

So i have this gauge and it's flashing numbers and letters and being all sorts of pretty colors but i dont know what any of it means. lol.. I'd like to understand what the car is telling me.

Anybody have any good articles i can check out? or advice to fully understand all the things this is flashing at me? lol

Thanks in advance.

the innovate is reading air fuel ratio by the use of an o2 sensor in the exhaust system. the numbers being displayed are the amount of air to 1 part of fuel. so the higher the number the leaner the fuel mixture. idling in the low 14 numbers is good. light throttle in high 13 numbers id good. low numbers like 10 or 11 is really rich, so depending on the tune the number range could be different.
hope this helps

thanks, Does help out, gives me a general idea. My car does idle around 14 ish but WOT is like 10's I beleieve. Car is not tuned yet, Has a walbro 255 in it which i know is over kill. Ordered rtek stage 2 but there not doing rx7 ecus until the 20th of june my tuning date is the 25, so hope to get it all settled and make some decent n/a#'s im hoping for around 175 to the wheels.

Anyone have a chart on what the other readings mean, like the letters that show up.

Maybe i can take a vid and post it.

Thanks for any input!

i have a chart.........need to find it and will post the a/r to co numbers

thanks man, i really appreciate it.

air ratio to %co
 

air/fuel %co
11.8 - 8.0
11.9 - 7.3
12.0 - 6.5
12.4 - 5.4
12.5 - 5.0
12.6 - 4.85
12.8 - 4.35
13.0 - 3.8
13.2 - 3.3
13.4 - 2.85
13.5 - 2.6
13.7 - 2.15
13.8 - 1.9
14.0 - 1.6
14.1 - 1.4
14.3 - 1.0
14.4 - 0.8
14.6 - 0.6
14.7 - 0.5
15.0 - 0.3

so whats like an ideal WOT range? in the 12's maybe?

i am seeing high 11,s with my set up

cool, thanks alot, I just wanted to have a general idea of what im looking at, I'm sure the tuner can explain to me more but that not until the end on the month.

Thanks again.

glad i could give you some insite as to what you are seeing. been using my wide band for tuning the carb a lot latley with the new engine....really cool toy to have. good luck on the tune and keep up posted

ideal will vary with the setup of the car, and your preferences. generally with the stock EFI and ignition, best power will be somewhere in the 12.5:1 to 13.2:1 area. the power difference between mid 12 and 13 is teeny, so on a street car i usually will leave it richer.

one of the limits of a stock ignition FC is the ignition power. the power the ignition can produce actually drops off @high rpm, due to there not being enough TIME to charge the coils fully. so it is very important that the spark plug wires be in good shape. mazda's spec is that they should be under 16K ohms/meter, and new wires are closer to 7k. the less resistance the wires have, the easier it is to fire the plugs.

i'll keep that in mind, i know i have new plugs and wires. Can we do like an msd box on these cars?

yep. not really need, but if you've got one