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Played around with an LM2 wideband data logger today

BlueCuda

NAXJA Forum User
Location
Tulsa OK
My Dad got me an LM2 wideband setup for my birthday last night. Its actually for my Barracuda but while the machine shop is holding the block hostage I figured I could fool with the LM2 on my Jeep.

My jeep is a 97 XJ with a budget 4.6 that has about 40K miles on it. Its got a Crane 753901 Cam and ford motorsport 24lb injectors, stock header, stock S pipe, after the S its 2.5" through a 2 chamber flomaster and out the back. Typical budget stroker combo for crank etc. I welded the O2 bung in just after the crossmember. The Jeep sits at about 4500lbs, 5.5 lift, 4.56 gears, locked both ends, aftermarket bumpers, tire carrier, 35" tires, sliders, tools, misc spare parts(was not trail ready). Actually with a driver and passenger it was probably sitting at about 5000lbs. I am mentioning this incase your wonderign why its so damn slow on the log below lol.

I was actually really surprised how good the air fuel ratio was, its 15:1ish cruising and at idle and averaged mid 12s wide open. I used the OBDII port to log RPM. Take in mind that today it was 106* on the overhead console. I was concerned that it would be a little lean as I get some spart knock now and then but now I know thats purely octane related most likely.

Here is the log, I started the log as I was turning around, the actual run goes between the two notepads on the bottom of the screen. Since I just got this stuff last night a screenshot was the only way I could think to post this.


JeepRPMAFRLog.jpg


I am curious what the WOT numbers will be like when the air is cooler, I imagine it would lean it out some since the ecu doesn't read the 02@WOT.

Anyways, i thought I would share. I would say I don't need a map adjuster.
 
I love my lm2. The complaints I have with it are having to scroll down through 8+ P0000s to get to real codes and that it can only handle 4-5 high priority channels before it bogs them all down. I got mine for $360 when they came out--how much are they now?
 
I thinkt hey are $400ish nowdays.

Mine only let me log one channel? I thought it was just a Jeep thing so I hooked it to my Wifes 05 Acura TL and it only let me do one channel as well, although it had many more options for that one channel. I wonder if I should give them a call about that?
 
You have to go to the obd2 section in the menu then you get to choose how many obd2 channels, what they are(rpm, cts, stft, ltft, ol, map, tps, etc), and then give them high priority or low priority(low checks them every other sequence).
 
I couldn't tell you talyn. They were in a friends mustang and I bought them from him, they have a blue top IIRC.

I Am curious about what it will look like in cooler air. I also have some lt1 injectors I would like to compare, but not until it's cooler. I was proud of myself for getting out in the heat and welding that bung in.
 
Your AFRs shouldn't lean out at WOT when the air temps cool. There is an intake air temp sensor to keep things in line. If that's stock ECU then the knock is a function of you stroking the motor.

What firmware is your LM-2? I used mine to tune an SRT-4 and the next time I tried to use it it read all over the place; firmware update fixed it right up. I'm on 1.14e and the last official release I was aware of was 1.15.
 
Reading comprehension error, lol. The injectors you have are a good match for your stroker build.
 
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Your AFRs shouldn't lean out at WOT when the air temps cool. There is an intake air temp sensor to keep things in line. If that's stock ECU then the knock is a function of you stroking the motor.

What firmware is your LM-2? I used mine to tune an SRT-4 and the next time I tried to use it it read all over the place; firmware update fixed it right up. I'm on 1.14e and the last official release I was aware of was 1.15.

I am going off the fact that at 106* ambient with the AC on its not hard to make something run rich lol. There is a good chance that with the larger injectors and the horrible weather conditions that it may not be able to pull enough fuel to lean it out. Its also probably rich at the top of the gears due to some unburned fuel from spark knock, I couldn't hear it but that doesn't mean its not there.

Yes I am aware the knock is from me stroking the motor, I am sure its got terrible quench as I didn't even check it when I put it together. I am itching to build another stroker and do it way different since I won't be rushed(was my DD at the time and it was broken). I would use a longer rod and a custom piston and actually check and adjust the quench as needed. I am confident if this thing had good quench I could get away with more compresion and not have the knock problem AND have more power :D. But this things been in there for 8 years and I could drive it to alaska tommorow if I had to so I am tempted to just leave well enough alone.
 
I feel the same as you in that the next stroker I build for myself(started building my brother's 4.9 with him on Saturday), I'll use long rods(have a box of Eagle 6.150s in my closet) and custom forged pistons with a 1.350" pin height(no cutting of the block) and low-mid 20cc dish. Gain knowledge and experience and use it to improve on the next one.
 
Ahhh.. I see what you did there.

Lol did I do something special? I have run stock, lt1, and the ford injectors. The fords have the best "feel" and now I know they have a decent afr.
 
I ran the older blue top/metal bottoms that had a single pintle and were rated 24#@39psi(27#@49psi) and my stroker didn't like them as much as the Black top/metal bottom 6-pintle lt1s rated 24#@43.5psi(25.5#@49psi). I've always been curious about those skinny all plastic blues w/ 4-pintles rated 24#@43.5psi(believe they are the "gen3"s).
 
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Mine are the blue top metal bottom, I have the black top metal bottom LT1s but its to damn hot to try them out.
 
I use the wifi OT2 with my Iphone, found it's not compatable with many different OBD2 systems, but luckily, it works fine on my 98" Xj and helped me figure out a few problems. I use the SSI4 with my PC at work, datalog various results, save the log records to memory, play them back later to customers. I am really impressed with the Innovate products, great tools for the price.
 
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