I'm finally making time to get back into working on my miata after YEARS of not doing anything to it. Right now it is all stock except for an LC-1. My first step was going to be re-calibrate the LC-1, then put the megasquirt in there and try to start tuning. Years ago I got it to start on the megasquirt, but at the time it was the wife's daily, so I couldn't screw with it too much. So, in trying to recalibrate the LC-1, I found it was dead (apparently their customer support communications are as well). So I'm in the market for a new wideband. Looking at either the AEM UEGO (based on how many happy users there seems to be), or the NGK AFX. But, the AFX is limited to an AFR of 16. So, my question is, how lean do people typically run their cars? Is 16 actually enough? Or would I need more range? In all the wideband discussions I have seen I haven't seen anyone mention what AFR range is important. Thanks in advance for your help!

 

I use the Innovate MTX-L, it has been great for the year or so i have had it installed. It reads from 7.35 to 22.4 AFR, I did have to set a custom wide band range in tuner studio to get the gauge and the MS to see the same values, but that took all of 5 minutes.

https://www.amazon.com/dp/B004MDT8MW...A15DTMM40CG6VX

 

You want more range than 16. Although you would never want to run that lean, more information is always better. I also have an MTX-L, and have been very happy with it.

 

Buy the AEM UEGO or an Innovative MXT-L.

 

I was burned once by Innovate, so I'm not looking to give them my money again. I am leaning heavily towards the AEM, and almost bought it last night, then saw posts saying that the NGK was also a good model and recommended by Greg Banish (though not as his first choice, but as an economic alternative to his first choice, which I believe was an AFM-1500). So is it very unlikely for anyone to be running at 16 or leaner during cruise? Based on one response so far, the answer is no. If so, then the NGK could be an option for me. I haven't researched it enough to know if I want one or not. I know it is more expensive, but if it is a quality sensor and controller for $100 or so more than the others, then I'd consider it.

 

Buy the UEGO, stop thinking about it. I would never touch a gauge that tops out at 16:1 afr. While generally you won't want to be leaner then 16:1, there are times you may be there during initial tuning and want to know what your afr is. For an example yesterday I was working on getting my AC filled. When my ac compressor kicked on idle would jump up outside of my normally tuned idle cells. It would go leaner then 16:1. I am not scared of something going wrong on idling like that, but knowing if I am at 16.2:1 or 17.4:1 makes it much easier to know how much fuel to add when it kicks in.

 

I am very pleased with ny AEM UEGO. You may need to stick a cap between it's power and ground wires since mine was noisy and made the stereo ring. Other than that, it has been perfect.

While I shouldn't be, my car occationally runs at >than 16:1. So nice to be able to measure it (still getting this tuning thing down.)

 

Also at cruising at steady state on the interstate I have ran leaner then 16:1 many times without issue. You don't really get better MPG so I don't constantly run up there, but depending on load it won't necessarily hurt anything.

 

The LC-2 is substantially better than the old LC-1, but if you don't want an Innovate product again, buy an AEM X-series.

 

X-series? Crap, I have more research to do. I was thinking the 4110. https://www.amazon.com/AEM-Combo-30-...words=aem+uego

Thanks for your help everyone. AEM it is. Now I just need to figure out if it is the X-series or the one in the link above. Thanks!

 

I have 3 of these and they work great. The X series has an extra digit of accuracy, but in the grand scheme of things that does not mean much.

 

I had the AEM UEGO and had several of the LED's die on me, but most people seem to have good things to say about them. I have an MTX-L right now and it has been working well for a few months so far. I would definitely want more than 16:1 AFR readings. I routinely cruise at 1.2 lambda on E85. But also as Lars said, even if you don't target above 16:1 AFR, you want to at least know where you're at if your actual AFR ends up above there.

 

They may not be super popular around here, but I've really enjoyed the PLX series of gauges.