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FLAMSP
09-13-2007, 01:34 PM
I recently installed an AEM wideband o2 gauge in my msp. What numbers should i be seeing. I am stock

Alexander
terbow
09-13-2007, 01:48 PM
cruising (not in boost) u should be fluctuating around the 14.7 mark, when u hit boost u technically should be seeing below 10afrs' on the msp but thats not usually the case unless ur gunning it up a hill (lots of load). at around 4k the msp will dump its fuel, you should be well into boost by then (not really a good thing but its the stock ecu). then it should go from 9.3 up to 10-11 afr by redline if ur stock. mods will change this so it really depends on what u have but u dont want over 12.3 in boost (in a nutshell)
livelyjay
09-13-2007, 03:18 PM
Please refer to the A/F readings at the bottom of this dyno graph. That should give you a good idea of what you'll see when gunning it.

Dynograph (http://www.csh.rit.edu/~jasonoff/pictures/dynographs/20050917/dyno01.jpg)
FLAMSP
09-13-2007, 05:30 PM
You guys rock, i'll go out for a drive later and let ya know what i get.
livelyjay
09-13-2007, 06:32 PM
This is a dynograph of my car, with the SplitSecond AFC and a custom map (http://www.csh.rit.edu/~jasonoff/pictures/dynographs/20051219/custommap.jpg)
This is a dynograph of my car, with the SplitSecond AFC and the super map (comes with the AFC) (http://www.csh.rit.edu/~jasonoff/pictures/dynographs/20051219/supermap.jpg)

As you can see, the custom map was a little safer. The A/F readings on the dyno are a bit leaner than what the true A/F reading is, because they use a sniffer at your tail pipe, and the cat and exhaust piping pulls some fuel out of the mixture before it gets to the sniffer. With the custom map I was around 11.5:1/12:1 through most of the power band.
FLAMSP
09-13-2007, 11:03 PM
So, @ full boost i was around 10 and idle around 14-15
terbow
09-14-2007, 01:41 AM
ur normal!
FLAMSP
09-14-2007, 10:05 AM
Nice, good to know i hooked it up correctly! So for a daily driven car what kind of afc should i get?
livelyjay
09-14-2007, 10:42 AM
The SplitSecond AFC is the best option for daily driving. It can be programmed with a laptop and is pretty easy to work with and install. There is a group buy being set up with now on the forum. I think the cheaper version as it will be better for you if you don't plan on going nuts with mods.