I just hooked up the LM-1 (Innovate's Air/Fuel Ratio Meter) to the WRX. The A/F sensor is screwed into the O2 bung before the cat-convertor. Here is the reading at idle, which of course is stoichiometric, 14.7:1, which is needed for cat-convertor efficiency. **Do you guys see the G-tech Pro RR on the windshield, I'll be testing this thing for accuracy at the drag strip!** Tomorrow at Rockfalls, I'll record the AFRs running down the 1/4 mile with the LM-1. It'll be interesting to see if all the gossip about the CAI is true or not. Not only this, I also have a GFB hybrid BOV installed, so I'll be able to see what happens to the AFRs in between shifts, which I'm going to guess will go lean for a split second, which is normal. I think the claim is that the car runs rich inbetween shifts. I might even bring along the stock air box with K&N to do a comparison study. But we'll see if I feel like changing out the intake at the track. I'll post results this weekend, so check back! Oh, and the mods are: AEM CAI Bosal Down Pipe & Cat-back, gutted stock up-pipe GFB BOV Cobb Accessport Stage 2 ECU flash.
AFRs of a 1st to 2nd to 3rd gear pull on a highway entrance ramp. I went full throttle 1st & 2nd, but lifted towards the end of 3rd gear & into neutral. The first spike on graph shows the 1 to 2 shift, second spike it the 2 to 3 shift and so forth. AFRs of a 3rd gear pull on the highway. From around 3500RPMS to redline, then lifted and went to neutral. These runs were done about a 1/2 hour ago. As you can see, under boost, there are no leaning issues whatsoever, just very RICH conditions. ***Does anyone know how I can convert a page on the monitor into a .jpg file?***
Not sure if it will do jpg but will do bmp (my Win computer is downstair and I am lazy tonight, running Linux here). Do a print screen and then open Microsoft Paint (comes with win) then do a paste. Say yes to resize and then crop and save if you want.
Can you plot afr vs. rpm? After we see that can an accurate conclusion be made. The Cobb maps are too rich on the top end to have any worries with a CAI. The problem area is where the turbo initially spools. IMHO, Cobb has this area too lean -- and who knows what can happen with a different intake.
To plot/log RPMS with the LM-1 I would have have to use LM-1s input-box, that needs to be purchased seperately (which I have), and would have to run a wire from a tach-signal to the LM-1 imput-box. This is too time consuming, so unfortunately, I won't do this. But regarding the issue about it leaning when the turbo initially spools, in my case, this is not true. If you look at the graphs that I provided, you'll see that the AFR slope goes down, meaning that AFRs are getting rich as boost builds & RPMS climb. Plus, with a passenger on board monitoring the boost gauge and the AFR meter at the same time, the AFRs richen instantanously as soon as you mash on the gas pedal, even before boost starts to build.
I was out at the track today, logging AFRs (air/fuel ratios) as the car wen down the 1/4 mile. I still can't seem to figure out a way to capture the data screen and put it into a picture file of some kind. I'll just take pics of the monitor screen and post them up later. All I can tell you guys right now is that with my setup & Cobb's Stage 2 w/91 octane MAP runs very RICH, low 10:1 ratios. (Been flashed at this state for about a week, so the computer should've had plenty of time learn what it needs.) Cobb Stage 2 on the 93 octane map gets it into the higher 10:1 ratios & lower 11:1 ratios, but this still is really rich. I'll give it a week and do a few dyno pulls on the highway.
Wow so the stories about leaning out from an intake install are false. Interesting, i might have to look into getting an intake once i get around to dyno tuning my car in cali. Thanks for posting this it's deffinitly food for thought.
So! What did you run at the track??? I have heard that the AEM intakes are the worst to tune well with. Nonetheless, it's good that you don't have any lean spots in the RPM band as boost increases. Your A/F ratio throughout the RPM band seems normal to me. I bet a dyno tune will do you very well. When I dynoed my Forester XT with an APS short ram intake installed, (of three runs) the first run was pretty lean and the second and third runs were really rich. I don't think it was the intake that made my first run lean, it probably was something else because it wasn't consistently lean.
IMHO, this thread has proved nothing. There still isn't any concrete data of rpm vs. afr vs. boost. Like I said earlier, the Cobb maps are very rich at 5000+ rpm under WOT. It's the area between 2500 and 4000 that concerns me -- especially under partial throttle. The Cobb maps will still hit pretty high boost numbers under these conditions and this is where most cars will experience knock with these maps.
It was from all of the water condensation in your exhaust. IIRC, it was puffing steam out of it on the first pull. Mine did the same thing (forgot to warm it up good, doh!) on the 1st pull and my AFRs were much leaner -- but it followed the same curve, just shifted upwards. That's my hypothesis.
I do realize that with the Cobb maps, boost does build up fairly quick under partial throttle. I was concerned in this area as well, which I too have monitered w/the wideband. Under the slightest hint of boost, the AFRs quickly richen. And yes, I do understand your point of not being able to log RPMs & boost, which make these claims hard to prove. But since I'm a nice guy, I do have the LM-1 aux. input device, which should enable me to be to log Boost & RPMs, I just have to do some connector backprobing in order to get those signals. I'll also log the knock sensor. If someone can get me a decent ECU pin diagram, I can backprobe for signals there. Otherwise, I can always go under the hood & head for the sensors themselves, but I rather leave those connectors alone. So.......here's the info that I need in order to data log the RPMs and boost. 1. A good wiring diagram of the inputs to the ECU. I think it'll be easier to back prob here for a reliable signal, for I'll be able to log what the computer sees. 2. Wiring diagram of the the under-hood connectors. So if someone can provide me with this information, I can get these signals logged. Gotta go the church this morning, but later this evening, I'll get the AFR charts from the drag strip posted.
In order to log RPMs with the LM-1, I also need to know a few things. 1. How many pulses are there per crank rotation? 2. How many pulses are there per cam rotation?
"Running lean improves fuel consumption and, at part throttle or cruise conditions, ratios of up to 14:1 can be run on the WRX without danger of detonation. At full throttle however, the AF ratio should be decreased (or made richer) to avoid detonation. Discussion with several specialist WRX tuners in Victoria, NSW and the UK proved interesting in that they all agreed the optimal AF ratio for the WRX at full throttle is about 12:1 for boost over 14.5psi. For lower boost, an AF ratio of 12.5:1 is acceptable and for cruise mode 14:1 is fine." ***quoted from http://www.airpowersystems.com.au/wrx/ecu_shootout/intro.html *** I'm aiming for mid to high 11:1 ratios. With a wideband meter, Cobb's Street Tuner, and the Gtech Pro RR (which I tested at the drag strip yesturday in multiple cars, it works!), I should be able to fine tune the WRX on the street, but this is a topic for another day.
Some 5h gear pulls on the highway, from 65mph-80mph, liight throttle applied, boost staying steady at 8psi.
So I'll stop here....there's no need to log RPMS or anything else. As you guys can clearly see on the AFR graphs, as soon as the throttle is applied, the AFR slope dips straight downward (rich condition). So the theory, or statement, that claims the AEM CAI causes the WRX to run lean at partial throttle/full throttle/initial turbo spool can thrown out the door. I gotta move on to more important things, like street tuning the WRX.
You have StreetTuner? Sweet. :biggrin: FYI, you should be able to hook the output of the LM-1 into the laptop, and ST will sync it with their logging and live tuning applications.
Oh yeah, that's exactly what I was going to do. For now, I'm spending time reading/learning as much as I can with the ST before actually going into it. I know Cobb has some decent MAPS to start with, but it'll be a learning process from there. Do you have the ST too?
I'm considering getting it, however I just spend some cash on a custom map from PDX. It rules. :biggrin:
Your best bet is to get familiar with the datalogging portion of the program and figure out how to integrate the LM-1 in with it. I'm sure it's pretty easy to do. Do you have an EGT probe?
12:1 is a bit lean for the WRX motor at high boost on our ****ty pump gas. That would be an acceptable A/F for race gas. You can go much leaner than 14:1 under cruise, stock they will want to run 14.7:1 under cruise, since that is the best A/F for emissions and is the A/F that most narrowband O2 sensors are calibrated for. The fuel tables in the factory ECU really don't support running leaner than 14.7:1, even though you could at cruise for better gas mileage.
