TRD 3.4L Supercharger Post Install Analysis and Tuning
Final Tuning Update:
I had a conversation with Gadget at URD after having my dyno runs made to understand why my AFR was more rich during the road test. He said this was pretty common and that the best way to tune a Supercharged 3.4L was to tune for the best power on the dyno, then do a road test. If the AFR shown during the road test was different from that on the dyno, then adjust so that the road test AFR matched that of the best power AFR from the dyno. As Gadget says in all his tuning docs, this ended up being right around 11.8 AFR.
A member over on www.yotatech.com recommended a very handy way of road tuning which I implemented with great success. Download a piece of free software called CamStudio. This software will record what your laptop screen sees and save it as an AVI video. In a nutshell you simply open the R4 tuning software, the Innovate Logworks software, and record their output using the CamStudio software. You then make a test run. Pull over, save the CamStudio video, then review. This will show you exactly what cell the fuel map is in and the associated AFR allowing you to dial it in perfectly. The only other way I know to accomplish this is to purchase an Innovate RPM Converter cable and splice it into your vehicle's ECU. I found the CamStudio method easy and un-intrusive.
Here's a video showing one of my runs as recorded by CamStudio. The CamStudio output is much cleaner than this video, but I had to recompress it as a WMV file so that it was small enough to be a web download and compatible with just about any Windows client.
Road Tune AFR video using CamStudio 900Kb
Here's my final AFR log from Logworks. As you can see, I'm right on the money. These AFRs were consistent and repeatable.
Update: I visited a dyno to check my horse power and torque numbers as well as to really focus in on the tuning. On the dyno I could do multiple runs and log the AFRs using my LC-1 connected to my laptop and the LogWorks software. After tweaking the map on the dyno, I then logged the AFRs during some road tests. What I found was that on the road, the dyno tuned map was too rich dropping down to 10.6 in some places. I believe this is due to the additional load on the vehicle from the wind/road resistance. I further tweaked the map and believe I have it set at this point.
Update: I checked the tune to see if it needed any tweaking after about 5,000 miles. I completed several WOT runs and the AFR gauge still stays right at 11.8 the whole time. I then hooked up the OBDII BR-3 and did some checking with the Diagnose software to check long term and short term fuel trims. They're good to go as well. I figured this was the case with how torquey and smooth the power delivery is, but it was nice to confirm it with hard data. Here's some screen shots from the Diagnose software. If doing your on tune checking don't expect the long term and short term trims to stay steady as it's the nature of the ECM to jump around, but they should stay pretty close to cancelling each other out such as in the screen shots below.
After installing the TRD Supercharger I completed more analysis of the vehicle to see how it reacted to the system before I started tuning. Prior to installation, I did some data logging with the OBD II BR-3 scan tool so that I could go back and compare after the supercharger was installed. There were a few things I was interested in such as fuel trims when cruising around, timing advance at WOT near red line, and intake air temperature. I did the logging on days with similar weather, which has been hot and muggy here in Middle Tennessee, with highs in the 80s F around 6PM with humidity around 40%. The mods to the vehicle were the deck plate being open and the ISR Mod.
Since I don't have a full blown data logger, I also used a video camera to record my gauges during several WOT runs NA (normally aspirated) as well as SC'd (supercharged). These video clips along with the BR-3 logging have been pretty valuable steps and will help out when tuning as I know exactly how the vehicle reacted to the supercharger.
The first thing I noticed was that I was getting some ping, which is common as the air intake charge is more dense and thus easier to ignite. The ping sound is the combustion process happening before the piston is at TDC (top dead center) and is a bad thing as it can blow a hole in a piston. I gave Project SportRunner 400 miles to adjust but it's wasn't able to compensate for the denser air charge the supercharger provided. The ping mainly happened during high gear low rpm as when climbing a hill and slowly feeding in throttle while in OD (over drive). The ping started around 2psi and continued until I got to about 2400 RPMs or so. Using the logs from the BR-3 from before and after the install as well as Gadget's U-Tune AIC guide I saw that the timing had dropped by about 9 degrees at WOT as shown in the screen shots below.
I installed URD's AIC-T (additional injector controller with timing control) that came with my URD 7th Injector Kit and added in the 9 degrees of retard at 7 psi and smoothed it all the way down to 0 psi. I then put 15 degrees of retard in at the max boost of the R4 tuning software and smoothed that down to the 7 psi mark. This is for extra protection should I have any boost spikes and is what is recommended in the U-Tune AIC guide. This base timing map I've loaded into the AIC-T has completely eliminated all the ping. I've tried my best to get any ping and can't even in 102 degree weather, lugging up a hill in OD, with the A/C on.
The next thing I took a look at were the fuel trims.
I learned from Gadgets U-Tune guide, as well as a former professional tuner who owned a SC'd 4Runner, that the fuel trims represent how much fuel is being added (positive values) or taken away (negative values) to maintain a 14.7:1 closed loop AFR (air fuel ratio). The key word there is closed loop as the fuel trims are ignored in open loop. In the SC'd log screen shot above, you'll notice the RPMs are higher than the NA screen shot. That was to make sure I got into boost as that would be the only place things would really show a change. The speed on the NA log is 0 because I didn't have that parameter enabled.
You can see in the log shots above that the fuel trims are pretty close in both cases. This shows that the fuel system seems to be dealing with the SC pretty well. If the values were very positive in the SC'd log, as in a short term of 8 and a long term of 6, that would indicate I needed to add fuel in this boost and RPM area to cancel them out. You add the short term and long term values together to get the base value, in the previous example 8 + 6 = 14, which means the vehicle is leaning out as it is trying to add fuel to compensate. In my case you can see the short term and long term fuel trims are both negative meaning fuel is being taken away and is very close to the NA value. This is kind of surprising and from my research NOT typical, so be sure to check your setup just as I did before assuming everything is fine.
I did some more WOT testing, this time in "L" or 1st gear for the auto tranny in Project SportRunner. I did lean out a little close to red line. The vehicle will never get to red line on it's own as it shifts before that point, but if you're a manual tranny, you'll definitely want to address that area.
I was running quite rich after the shift into 3rd gear dropping all the way down to 10.0 at WOT. After installing the URD AIC-T with Integrated AFR Calibrator this has been mostly corrected. I did some additional testing after tuning the timing in the URD AIC-T. I'm not sure if it's the timing or the AFR Calibrator, but one of the two really helped my problem with running rich. I'm now hitting no lower than 10.9 AFR at WOT in 3rd. I used the LogWorks2 program to record the following run from 0 - 100 MPH at WOT. The spikes are the shifts between 1, 2, 3, and 4th gears.
I installed the 7th injector part of the kit next. The install was VERY easy and everything fit just as it should. I've only dabbled with tuning thus far, but it seems to be a pretty easy process. The hardest part is trusting someone to drive Project SportRunner at 100MPH while I watch the laptop. So far I'm only needed to add just a very small amount of fuel near redline in the RPM range. My vehicle did not require the included Walbro 190 pump, surprisingly.
Next I installed the 2.2" URD Supercharger Pulley which increased boost from 7 psi to around 9.5 psi. That should add another 20 - 25 RWHP. With what I've seen so far from an AFR perspective, the 2.2" pulley should be a near perfect match for my setup.
Finally, I went out to do a full tune on the system. I had my girlfriend drive Project SportRunner on a very desolate section of highway where we could cruise along, go WOT, slow down, speed up, etc as needed to get all the tuning complete. While she drove I would listen for ping, watch fuel trims and timing adjustments in the Diagnose software as well as the fuel and timing maps. I'd make adjustments, have her pull over and shut the truck off, I'd upload the new map, and we'd start again until I had the truck doing what I wanted.
This process took about 2 hours to complete and actually was pretty easy once I got the hang of it. My advice is to make adjustments in VERY small increments and focus on very specific map areas to keep from getting overwhelmed. For instance, start at 1psi, get it sorted, then go to 2psi, etc. Once I had it tuned pretty close, I decided to drive it for a while to give the ECM time to adjust to all the new information and the tune got even better. Now when I give it WOT the AFR drops to right around 11.5 - 11.8 and will climb to just about 12.0 right before a gear shift which is perfect. I get zero ping and the power is very surprising and brings a huge grin to my face. When driven reasonably, gas mileage stayed almost exactly the same as stock at around 20 MPG. When driven more aggressively I'm getting between 17-18 MPG which I consider VERY good for the amount of fun involved.