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.


[IMG]local://upfiles/9095/F45108A9B75243909211D29434989108.jpg[/IMG]

[IMG]local://upfiles/9095/42FE4873F9634232AE281CAA6670DEBD.jpg[/IMG]

 

Looks good Silver! Once you get the ARC1 in may want to take it to the dyno and see what kind of affect it has so you know what the best settings are Nice to know what you have for rwhp, and how to get the best mpg or hp with it.

 

Is it mounted with double sided tape of some sort? Not to steal the thread, but did you changed your gauge color somehow or does it jst look like that in the pic......my gas gauge hasnt been that close to full in a while

 

That's a good idea. Been wanted to get it on a dyno anyway. Do you think 12.5:1 is too rich for WOT? I noticed this morning after it was fully warmed up, WOT was closer to 13.2:1. It would dip down to 12.5:1 for just a moment , but come back up.


Ya, unfortuanly, they do not provide any mounting hardware other then these little velco strips to mount it with. Not my prefered mounting option, but it works ok for now. I am probably going to fab up something that looks better, but not in any hurry to do that yet.
No, that is the color my guages have always been. They have a greenish color. My trans temp gauge (on the steering column) is different because that is aftermarket.

 

Foul! FOUL... no way is that your dash/truck... it's too damn clean nobody can keep their dash that clean! <jk>

Nice install! what does it read when your cruising on the hiway?

 

sweet, how much that cost?

 

Ha. If you've ever seen my engine bay, you already know I am a little **** about keeping my truck clean. You would think I have OCD or something, but my vehicles are the only thing I keep clean like that. [&:]

At cruising, since it is a closed loop mode, it dithers back and forth between 15.5:1 and 14.2:1, with the idle ratio of 14.7:1 being right in the middle. The speed and consistancy of the dither tells you how well the PCM is doing dialing in the A/F. In closed loop conditions, the PCM is constantly adjusting the injector pulse width to maintain an ideal a/f. Since these changes are happening very rapidly, the meter can not lock into a specific a/f ratio, so it dithers as the PCM is making adjustements.

It does, however, lock into a specific a/f reading once you go into WOT or other open-loop mods though. This is because that is when the PCM starts ignoring the o2 sensor input, and goes strictly off of its preprogrammed tables. These are the tables that programmers and flashes change, thus adjusting the a/f ratio perminantly during open loop operations. I think this is one reason why most programmers say they are only for stock vehicles. By adjusting the preprogrammed settings, the PCM has no choice but to use those settings. The programmers build these to work with stock air intakes, TBs, etc... If you go changing that stuff, you could throw off the a/f ratios at WOT and other open loop modes because the PCM is stuck using what is in the table at those open loop times.

 

New from Split Second, the ARM1 runs about $140. I got mine off eBay for a little under $100. It was unopened in the original box. The calibrator (ARC1) runs for about $210. I also got it new off eBay for a good price.

http://www.splitsec.com/index.html

 

silver_dodge, now i am interested in seeing how clean you are under the hood. i know i always get comments about mine. im the only person i know that uses tire shine on everything under the hood about once a month.

 

Look at the link in my sig or in my gallery.