The word “gearhead” encompasses a lot of territory. Though people with no interest in cars at all (except as transportation appliances) might lump us all in the same category, there’s a wide range of different interests, skills, and experience levels that fall under that moniker. Some will never do more than casually turn wrenches in their spare time, while others will dive in with both feet and strive to explore even the most esoteric aspect of their hobby, or even turn it into a profession.
For the latter, late model EFI engines are both a blessing and a curse. A curse, because for the most part, they don’t require the kind of hands-on attention previous powerplants demanded. There are no points and condenser to change, no carb jets to swap, and no distributor to gently nudge until the timing light shows you’ve got it perfect. For the most part, late model engines just run. If they need something, it will probably be because a sensor has failed, and parts replacement is all that can or should be done.
But the blessing for those willing to really devote themselves to study and practice is that EFI opens up literally every aspect of the engine’s operation to inspection and modification, if you have the right tools. While getting a carbed engine tuned and tweaked was part science, part witchcraft, there’s no corner of the performance envelope for an EFI engine that can’t be put under a microscope and examined in complete detail.
Digital Swiss Army Knife
For digging deep into Gen III and Gen IV GM engine management, one of the most popular tools currently available is EFILive. We’ve recently added it to our resources here at LSXMag, and to get some insight into the history and capabilities of the system, we talked with Dave Emanuel, president of Digital EFI, a US distributor of New Zealand-based EFILive’s products.
Emanuel has been working with electronic fuel injection in its various forms for a very large part of its existence, and has seen the tools available to view and alter factory programming evolve over the years. “I’ve been doing this since the chip days, doing EFI tuning since 1994,” he explains. “I’ve been through the whole progression of it.” Back before the government-mandated OBDII standardization made programming via a reflash practical, one common strategy was to “chip” the ECU – basically rewriting the computer’s programming on a replacement microchip, and physically replacing it inside the computer.
Today’s tuners who never had the dubious pleasure of cracking open an ECU case just to change the tune might not appreciate just how easy they have it with integrated datalogging and programming tools like EFILive. Emanuel recalls, “I used to tune with a program called LS1 Edit, and datalog with EFILive – when it first came out it was strictly a logging program. And I remember thinking, ‘I wish they’d come out with a tuning program.'”
Well, sure enough, the Kiwi enthusiasts (as in, “enthusiasts who are colloquially called ‘Kiwis’ because they are from New Zealand,” not “people who are enthusiastic about small, exotic fruit and/or flightless birds”) behind the original, logging-only EFILive system evolved it into a full flash tuning suite, suitable for pro-level applications. “Originally it was LS1-only, and then it became controller-dependent,” Emanuel explains. “After the LS1, GM went to computers that were designed for broader applicability. If you can do an E40 ECM for a Corvette, well, then you can do an E40 for a Trailblazer. That’s how it proliferated, and then the diesel stuff hit. That’s been a whole different thing altogether, and that’s the really vibrant portion of the performance market now.”
Hardware and Software
The current incarnation of the EFILive LS tuning suite is actually a combination of both a physical device that interfaces with your car’s computer, the FlashScan V2, and the EFILive software. Depending on what you’re doing, you might use the FlashScan by itself, or in concert with your laptop loaded with the EFILive software. “It started with the V1, which was very much the same as the V2 in terms of the pass-through functionality, but it didn’t have the capacity to do any tuning directly from the box,” Emanuel recalls. “[With the V1] You did everything from the laptop. The real difference between the V1 and the V2 is the black box capability, where you can read and reset trouble codes, download and upload calibrations to an ECM, and datalog (without a computer). It adds another dimension to the tool.”
The FlashScan connects to your vehicle’s computer via the OBDII port located under the dashboard, and as Emanuel pointed out, it can perform a wide variety of tasks while untethered. A slot accepts standard SD cards to provide storage for datalogging, and there are multiple additional inputs for other sources of data: K-type thermocouples, 0-5 volt sensors, and wideband oxygen sensors are all natively supported by the FlashScan V2.
Pro Tools for Everyone
There are a surprising number of people who are doing their own tuning – it seems to be moving in that direction. – Dave Emanuel, Digital EFI
“I handle any questions we get,” he explains. “We do get people calling about becoming a dealer, when really what they want to be is a tuner, and they don’t understand you don’t need to be a dealer to sell tune files.” For those who know what they’re looking for, Emanuel says that EFILive offers some advantages in ease-of-use and workflow over the competition. “The biggest advantage is kind of a double-edged sword. It’s more user-friendly once you get past that learning curve. You have to be more involved and more technically knowledgeable than you would with something that was more plug-and-play, but that setup gives you much greater capability. You have to be more literate, both computer and engine function literate, than some of the others, because you have to understand what all the tables do.”
Roadmap to Success
Becoming comfortable with a particular piece of software is often predicated on whether it “works with you” or makes you have to remember things that should be handled automatically. Emanuel points out that EFILive is put together with a lot of seemingly small features that make a big impact on the efficiency of getting things done. “One of the things that’s nice about it is that every table is numbered,” he explains. “So if I am working with somebody and they say, ‘I want to change the fuel flow table,’ there may be several fuel flow tables. Timing tables are another example – you’ll have a high octane and a low octane table, in gear tables… so rather than being confused about exactly what one you’re working on, you say ‘I’m having a problem with table B4001’, and there is no mistaking it for anything else. You can go right to it in the navigation bar. You don’t have to search and open up each tab and ask, ‘is B4001 in here?'”
“There’s a number of really good compare functions, and modification functions where you can modify by percentage,” Emanuel continues. “I can go in and highlight some cells and, say, increase or decrease by one percent, two percent, five percent, whatever, or alter those cells by a specific number. With the compare functions, I can pull up another program I did for a different customer, and say, ‘this vehicle I did for John is very similar to the one I am doing for Harry, so let’s see what that one is like in comparison.’ Or I can take part of John’s program and do a copy and paste to Harry’s.”
Besides just doing tune-to-tune comparisons, EFILive can also call out links between logged data and the tune file. Emanuel says, “The other thing I think is really helpful is that I can go into a datalog and I can highlight an area of that datalog that I want to address, and when I go back into the tune file, the cells that are controlling whatever I am looking at in the log at that point are highlighted. If I’m driving along and see I am having a problem just off idle at 1,500 RPM, and 75kPa, I just highlight that area. When I go back to the table, it shows me exactly what cells were in control of fuel, spark, or whatever. It’s tremendously well thought out from a user standpoint. It also keeps a history of every change you make. You can also put comments in every time you save it. You open the file again and you know right where you are and what you did.”
Searching for Stability
In our particular case with Project Y2k, our 2000 Corvette, we were particularly interested in working on drivability issues using EFILive. After a series of modifications, including a new intake manifold, long tube headers, and a cam swap, we had an engine that made very good power and torque throughout the rev band. What it didn’t do, though, was settle into a stable idle when the air conditioning was blasting.
Sure, for a pure race car, that’s not even a consideration. But for our Blue Collar Supercar, stalling out at every traffic light on hot days isn’t acceptable. We were part-way to a solution with the help of a pro tuner who spent an hour or so previously, tweaking the fuel tables to compensate for the EGR effect of the new cam’s overlap. But we really needed to spend some time with the other parameters that control the idle stability of our LS1 powerplant.
We started by hooking up our FlashScan and connecting it to the laptop, then firing up EFILive’s scan tool software. Identifying our PCM, we picked the Performance Information Data (or PID) channels we wanted to monitor, then did a bit of datalogging under the exact conditions we were having trouble with.
One of the great things about having your own EFILive system is that you can very easily log and tune for the entire operating range of the engine at your convenience, rather than rushing during a dyno session to try to get as much out of the limited time on the rollers as possible. Paying a professional to spend the time to sort out intermittent drivability problems can get very expensive, very quickly, making the investment in your own hardware and software quite cost-effective if you are willing to educate yourself on how to use it properly.
After looking at our logs, we found some specific tables we wanted to tweak. Specifically, we tackled the B4603 Desired Idle Speed table, which previously had the same values for AC on and off, and bumped up the idle speed for when the air conditioning was active, and also adjusted the values for B4612, which is RPM Set Point Adjust In Gear, and B4614, RPM Set Point Adjust Timer. These two calibrations control how much and how often the PCM adjusts the target idle speed, respectively.
Calibration saved to our laptop, we reflashed the PCM on Project Y2k through the FlashScan, and were rewarded with improved idle stability while the AC was pumping. It’s still not perfect, but the beauty of the scanning and tuning capabilities of the EFILive system is that we have a tool that gives us the ability to adjust literally every parameter of the engine’s operation until we’re satisfied.
Science, Not Magic
I said, ‘you will have people come to you who will say, ‘I have a rod sticking out the side of my block, but you can do a chip for me that will fix that, right?’ – Dave Emanuel
“This was back in 1999, 2000, that timeframe,” Emanuel recalls. “A guy I’d been doing some mechanical stuff with tells me, ‘I’m going to start doing tuning – I’m gonna do some chips.’ I said, ‘you will have people come to you who will say, ‘I have a rod sticking out the side of my block, but you can do a chip for me that will fix that, right?’ We laughed about it, and then about ten years later I was talking to him again about some stuff and he says, ‘there isn’t a day that goes by that I don’t hear those words again…'”
EFILive won’t patch a windowed block, but it’s an essential tool in the arsenal of anyone who is serious about working on late-model GM engines. With so much of the powerplant’s performance and drivability dependent on the tune, the full access provided by EFILive is a necessity for serious automotive professionals, LS racers, and even well-equipped do-it-yourselfers.