attn J could use a little info on your A/F gauge plz

Devin said:
Edit: "at wot will only show you the commanded lambda in the base fuel table" I am not even entirely sure what this means. I am pulling signals straight from the 02 sensors, what the ECU is doing isn't part of this metric..
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The ECU is absolutely part of the equation.
At WOT what you are seeing is the "commanded" lambda that the PCM is commanding.
If you dont know what that means, you really should do a little research.

anything less that WOT the 02 sensor voltage switches back and forth as mentioned above...AT wot it's not showing your AF ratio.. it's showing what the PCM is commanding for AF ratio.. which might be 12.5 to 1.. but that doesnt mean the CAR is DELIVERING 12.5 1.. only that the PCM is "shooting" for 12.5 to 1.

It's all pretty simple.. the narrow band 02 sensors do NOT show AF ratio at ANY POINT or TIME.
 
bryantaylor said:
ALL a narrowbad provides the ECU with is a "switchpoint" for cruiseing. not a certain AFR under WOT.
.
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ding ding ding! we have a winner!

Bryan understands this.

Now at WOT the PCM commands a particular AF ratio, depending on what is in the "base fuel table"....but that doesnt mean the car is actually "delivering" the commanded AF/lambda ratio.
 
(quoted from the article linked below)

"The affordable meters on the market, at the time, used conventional narrow
band O2 sensors- the same type of sensors found in most early EFI cars.
Such sensors are only accurate around the stoichiometric range, which is an
air fuel ratio of 14.7:1. Accuracy in this range is useless for performance
tuning where wide-open throttle ratios may drop as low as 11:1, and
certainly in the 13:1 range for most naturally-aspirated engines."

http://tunertools.com/articles/FordMuscle.pdf
 
The beauty of a WB02 is they can be run in what is called "NB emulation" in which it "emulates" the activity of a narrow band sensor.

So you can pull one of your stock UPSTREAM sensors and run the WB sensor in it's place..and in emulation mode, it'll still supply the PCM with the NB02 data, while providing your guage with the WB 02 data.

That way you have a REAL A/F guage displaying your REAL A/F.
 
see, i knew i wasn't crazy, lol.

but a wideband is only like $300 now, and if you have ever used one you know that its WELL worth the money. i have had my AEM ugeo for quite a while now and wouldn't attemt to tune without it.
 
There's some good info here besides real warnings and not opinions. Only real way to monitor your a/f ratio is with the proper wide band setup. Yes they are getting cheaper but you have to look out. You get what you pay for with these. I've been through a lot of different makes and models throught the years. I have a pile of junk units. My old stand by is the Innovate LM-1. The only times it has failed me is when letting someone else use it. But since I'm an autherized dealer for them they give me a break on the repairs. They now have the new LM-2 that I've had on back order for awhile now but was told I should have them in a couple weeks. This unit will allow you to plug into your OBD II port and pull down 16 additional data signals such as rpm and TPS and record them for later play back and tuning. This won't do the OBD I guys any good but they can still data log using the converter that takes any 0 - 5 vdc input and logs it besides rpm.

There are some really good units out there, don't get me wrong. It's just that the really good ones will run you $1000 - $3000 or more.

I carry the LM-1, LC-1 and LC-1 XD-16 and soon the LM-2. Besides all their support parts.
 
The LC-1 is a great entry level tool for what..a couple hundred dollars?

it really doest make sense to "save money" on this type of thing.
 
bryantaylor said:
i had a LC-1 when they first came out. it was the biggest peice of crap, sold it and bought a AEM and could't be happier.
Click to expand...

The LC-1s are at times a pita to program but once you figure it out they work pretty good. I've had an AEM that had failed on me and was sent back, it still isn't reliable and so I use the LM-1 for all my street/track and backup for dyno. An easy to follow setup for the LC-1 can be found here LC-1 to XCal 2 setup

Have you read this yet Wide Band kit compare
 
this pic is awesome, LOL

lead.jpg
 
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