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Mmmmmmmmm, beer.
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Well, I finally got enough time to go out and install my Split Second ARM1 (Air/Fuel Ratio Meter). I drove around for about 20 miles or so after the installation and I learned that my truck seems to be operating fairly good from an air/fuel ratio perspective.
-At cold start-up and idle, it is rich, but after it warms up, I dither right around the ideal stoichiometric air/fuel ratio of 14.7:1. A consistant dither speed that is close to 14.7 means the PCM is doing a good job of dialing in the air/fuel ratio while in closed loop mode.
-At cruise speeds (still closed loop), I am in that same ideal range still (good for fuel economy like that).
-The point where I have noticed that I seem to always have the most power (mid rpm, about 1/2 to 3/4 throttle), I am at about 14.5:1 to 14.2:1, just a tad rich. That might explain why it seems to have the most power at that time.
-Lastly, at full throttle (open loop), I am very rich, at least 12.5:1 (not sure how rich for sure, that's as low as it goes on the meter). I expected it to be rich at WOT, but not sure if I want it that rich. I does a good job of reining that in after a few seconds, though.

Next install will be the Split Second ARC1 (Air/Fuel Ratio Calibrator), which will let me manually adjust how rich I want to run in various modes (open loop, closed loop). I'll be able to dial down that WOT richness, and we'll see if that makes any difference.

Here's some pics. I mounted it high so that I could watch it without taking my eyes off the road to much. I think I may install a switch with it so I don't have to have it going all the time, just when I want to see how things are doing, or I need to make an adjustment.
 

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Nicely done. Does that tach get in the way of your speedo at all? Sucks that you have that huge fuel gauge and not the stock tach :(
 

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Mmmmmmmmm, beer.
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Discussion Starter #3
That's not a tach, its my trans temp gauge. No , it doesn't block anything. The camera angle in that picture makes it look like it is in the way, but when you are actually sitting up in the seat, it does not get in the way.

I have thought pretty serious about changing my gauge cluster out for one with the tach (the PCM is already wired for it), but the problem is with the odometer chip. It's illegal to tamper with it.
 

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Sorry, the second pic didn't even load before I scrolled down to comment! The flash on the cover of your gauge blocked all the numbers, so I just figured it was a tach since you didn't have one stock. I saw your thread on the cluster swap, I am curious how that would work out with the mileage and everything. I have a stock tach so I am not looking to change mine out, but I am always curious about stuff like that. Let us know what you decide!
 

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Mmmmmmmmm, beer.
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Discussion Starter #6 (Edited)
Big Joe SS/T said:
FYI air fuel gauges are useless with out a wide band 02 sensor, there just a blinkey light thing that sweeps side to side.
Well, I disagree with your statement, and as usual, you come in and spout some useless BS comment without any information to back it up. Very helpful. :WHT: This is why I ignore most of your posts, you never have anything useful to contribute.

Well let me then be the one to provide some helpful information. The difference between a narrow band and wide band o2 sensors is in how the sensor converts readings into voltage output. The stock narrow band sensor operates between 0 and 1 volt. This means it can positively identify a rich or lean air/fuel condition, but only within a range of about 12.5:1 to about 17.0:1. A wide band sensor uses a more sophisticated sensing element which enables it to produce more precise voltage readings over a wider range. This lets it identify a/f ratios from as low as 9.0:1 to highs well beyond 17.0:1

So let me go back to your original broad statement that "air fuel gauges are useless with out a wide band o2 sensor". That actually depends a lot on why someone has an a/f gauge to begin with. If it is to identify a lean or rich condition on a naturally aspirated engine running on pump gas, then a narrow band does precisely that. If it is to accurately identify the exact air fuel ratio each moment, especially outside the range of 12.5:1 to 17.0:1, then a wide band is the best way to go for that.

So lets look a little closer at my particular install. Oh look, I only did this set up so I could see if I had any rich or lean conditions, not to accurately identify my exact a/f down to the hundredth of a decimal. And crap, look at that, my truck is still naturally aspirated and I am running 91 octane pump gas. Will I be operating outside of the range I mentioned above? I better not be, or I will have more problems then just not having an accurate enough a/f meter. So, is this meter useless to me. Not at all, in fact it does exactly what I bought it to do. The only useless thing I find here actually is your post.

Also, you seemed to conclude in your response that all it takes for an a/f meter to not be useless is a wide band o2 sensor. That too is incorrect. Just because you have a wide band o2 sensor, does not guarantee that you are getting an accurate reading. The a/f meter you choose to use with that o2 sensor must be calibrated correctly to understand the readings coming from the o2 sensor. A wide band sensor by itself is not the only factor for getting accurate a/f readings.

So, maybe next time before you blab some comment that is neither helpful nor accurate, you will do a little research and understand both the topic and the specific reasons behind why someone did an install or chose a specific type of product for their use.

Thank you, come again.
 

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Nice :nutkick: Silver, may want to put some ice on them Joe :D

As I mentioned on another site, looks good. Once you have the arc1 in may want to reduce the low load trim to 15.0-15.5:1.
 

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lol.
 

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So is there already a PCM output for hooking one up? I know some cars already have the output to hook to.
94 1500 5.2
 

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Mmmmmmmmm, beer.
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Discussion Starter #11
The meter does not tap into output from the PCM, it taps into the output from the pre-cat oxygen sensor. It just connects to the o2 sensor output wire, and the o2 sensor ground wire. Not sure if it is the same on your '94, but on 99-01, these wires come into the PCM on the right hand plug (as you look at the PCM from the front). One is tan with white tracer and the other is black with light blue tracer. It is also the same on a '97 (I know of a guy who did this same install on his '97, and the wires were the same).
 

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Silver_DodgeRam said:
Well let me then be the one to provide some helpful information. The difference between a narrow band and wide band o2 sensors is in how the sensor converts readings into voltage output. The stock narrow band sensor operates between 0 and 1 volt. This means it can positively identify a rich or lean air/fuel condition, but only within a range of about 12.5:1 to about 17.0:1. A wide band sensor uses a more sophisticated sensing element which enables it to produce more precise voltage readings over a wider range. This lets it identify a/f ratios from as low as 9.0:1 to highs well beyond 17.0:1

So let me go back to your original broad statement that "air fuel gauges are useless with out a wide band o2 sensor". That actually depends a lot on why someone has an a/f gauge to begin with. If it is to identify a lean or rich condition on a naturally aspirated engine running on pump gas, then a narrow band does precisely that. If it is to accurately identify the exact air fuel ratio each moment, especially outside the range of 12.5:1 to 17.0:1, then a wide band is the best way to go for that.
Actually a narrow band O2 sensor is notoriously inaccurate at just about anything other than 14.7:1 (speaking gas here). It will give you an indication of lean or rich relative to 14.7:1, but past this there is not much accuracy. As you stated, if this is all you are looking for then that works. If you are actually trying to tune a motor, then this is not sufficient enough.

Some very good information for tuning (O2s and otherwise)innovatemotorsports dot com

Klaus, one of their main engineers who frequents the forums, is VERY helpful with tuning questions in general. They also make some very good products.

Brian
 
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