CoolGuy094

OK, so apologies first of all if I don't know what I'm talking about; electronics is my weakest field. Here is what I want to accomplish. I want an easy way to view my A/F information in a way that I can review and use it to make minor modifications on my AFC Neo in an attempt to smooth out my A/F curve throughout my RPM range. My header has an available wideband bung, and I know I need a sensor here. I need to know what sensor is recommended here, and what I can use to obtain my A/F info. Do I use just a gauge? I would really like something that could record the A/F info and make it plot-able or export to data points or something similar.

Sorry, I am sure there is something capable of doing this, I just don't know what I need yet. Your recommendations and expertise are welcome.

liquid_helix136

I'm not the best when it comes to all this junk either, but I've got a wideband (AFR gauge) and have been looking into doing a little self tuning myself.

Innovative wideband or AEM wideband is what your looking for. My wideband sensor is in a bung I had welded onto my test pipe, however my header doesnt have a bung on it, so you could use that. If you wanted to datalog your AFRs (the info so you know what to change and where to change it) you will need a more advanced EMS like a GReddy EMU (wont work with the AEM wideband, as this is the route I was going to go) so a flashpro/kpro, Haltech ecu or AEM EMS would work better with Flashpro being the best option if your 06+

However there is a good bit more to tuning than just fixing AFRs

Hope this helps a bit

Anyone feel free to correct anything I didnt get right / missed out

jh4db536

You need a datalogger and a wideband/controller. For wot all u need is rpm vs afr.

Its much easier to buy an ems like a aem, haltech, or kpro because everything is built into it.

If u really want to continue with that piggyback, innovate has a handheld wideband unit that plugs into the obd port to get the other data.

http://www.innovatemotorsports.com/products/lm2.php

Sent from my T-Mobile G2 using Tapatalk

CoolGuy094

Thanks to both of you. Unfortunately I can not go with a standalone or kpro thanks to the restrictions the SCCA places on the AP1's in STR class. The AP1's are limited to piggybacks, the "best" of which is the emanage ultimate. I didn't feel like the slight benefits of the emanage would truly help me any more compared to the AFC's capabilities to justify the price difference. Also, I don't know that the emanage would have gotten me AF data either (would it?).

It looks like the LM2 will do exactly what I am looking for. Looks like they go for about $375 on Amazon as well, which isn't too bad. It would also be a useful tool for OBDII purposes, as I don't currently have a code scanner. I will look into it. Thanks again guys.

User 121020

jh4db536, if I'm not mistaken (which is possible), the standalones you mentioned do not feature integral wideband controllers. You would still need an external wideband controller but could input the wideband signal directly to the standalones and use this signal for closed-loop fueling control or monitoring.

CoolGuy094, here's my attempt to explain widebands & their controllers...

The wideband O2 system differs from a narrowband O2 system in that it has a much larger and more accurate range of O2 measurement. A narrowband O2 system has a highly non linear output between 0 & 1 VDC. Basically, the narrowband O2 sensor acts like a switch between 0 and 1 volts depending on whether it measures values greater than or less than 14.7:1 air fuel ratio. Here's an image that shows a curve that corresponds to a typical narrrowband O2 sensor output (snagged from google images):



A wideband O2 system, on the other hand, has a relatively linear output signal between 0 & 5 VDC. Here's a plot from Innovate Motorsports LC-1 output settings software, showing the output calibration of their controller:



The larger range of output voltage and linear output curve provides much better resolution and accuracy of the air:fuel ratio. This allows tuners to have much better knowledge of what the engine is doing.

So, now that we understand why we want a wideband O2 system...let's get into the controller stuff. As the previous post mentions, you need to be able to data log the air:fuel readings and correlate them to an RPM value. This will allow you to plot the AFR values with respect to RPM and see where the engine is running rich or lean. There are a few ways to achieve this.

A standalone wideband system, such as the LM2 mentioned earlier, can monitor both RPM and the wideband O2 signal. I have one and it is how I tuned my system when I used a VAFC. This system also gives you the ability to monitor other OBD2 channels. For an AP1, the sample rate starts to get too low when you monitor more than ~3 channels through the OBD2 port. The AP1 ECU doesn't communicate to the OBD2 port as frequently as the new '06+ AP2s.

The other approach is to use a wideband controller (like the AEM UEGO, Innovate LC-1, etc.) to provide a means of accessing the 0-5VDC output signal. It _is_ possible to connect this output signal to the Greddy E-Manage Ultimate and have it recognized as the AFR signal. This is exactly what I am currently doing with my EMU. It works great. The EMU can then be used to data log and monitor many different channels at a relatively fast sample rate. So, through the EMU logger, you can log and monitor RPM, AFR, and whatever else you'd like to monitor at a 50Hz sample rate. That equates to a reading every 0.020 seconds, which is plenty fast for characterizing the fueling behavior. I documented a couple of tips for connecting an external wideband controller in the STR ECU Discussion thread.

Hopefully most of the above makes sense.

jh4db536

Yes if you want to get technical you're correct. All of aems wideband kits whether its the gauge or the inline wideband have a controller (its addtional product and not required to run ems). The idea is the logging ability external and internal is inherently in the ems and related software for analysis. You can plug in a whole array of aftermarket sensors to log data beyond the stock sensors or at a higher resolution/accuracy ie wideband per cylinder, egt, fuel pressure, etc.

Sent from my T-Mobile G2 using Tapatalk