Due to the EU’s Global Data Protection Regulation, our website is currently unavailable to visitors from most European countries. We apologize for this inconvenience and encourage you to visit www.motortrend.com for the latest on new cars, car reviews and news, concept cars and auto show coverage, awards and much more.MOTORTREND.COM

Is Diesel Tuning Dead?

Tune Up

Jason Sands
Mar 28, 2019
Photographers: Jason Sands
Mainstream diesel performance hit a home run when Dodge introduced the Cummins-powered Dodge Ram in 1989. In stock trim, the trucks were reliable yet underpowered, but it wasn’t long before enthusiasts figured out the 5.9L 12-valve engines could be "turned up" for increased performance simply by turning a screw in the injection pump to add more fuel, which often resulted in gains of up to 100 hp—and usually a lot of exhaust smoke.
This method of tuning continued until the late ’90s, when manipulating a diesel’s fueling started to evolve. Dodge went from using mechanical VE and P7100 injection pumps to the VP44; a rotary pump controlled by the ECM.
Early electronic tuning basically involved “tricking” an ECM into adding more fuel, timing, or both, and it was all achievable through simple boxes that hacked the stock processor. Ford's 7.3L Power Stroke engine could be modified in the same way, and some companies like TS Performance even offered chips programmed with different calibrations that could be changed by turning a multi-position switch. GM’s 6.5L oil-burner was also computer-controlled at that time, but the company’s 6.6L Duramax LB7, introduced for 2001, is the engine platform that lead the charge in changing the way we do things with diesel tuning.
The new engine was released in ¾- and 1-ton GM pickups and instantly became an industry leader. It had the most power in its class (300 hp) and a sophisticated computer capable of infinitely tuning the engine. Performance-minded enthusiasts also quickly realized this advanced powerplant was extremely limited with the stock calibration, and by simply raising the amount of fuel, timing, and boost, gains of an incredible 200 to 250 hp on otherwise-stock trucks could be reached. The discovery led to two things: the birth of a strong aftermarket transmission industry (as this was now the weak link) and a flood of aftermarket programmers and tuning for this new and exciting engine.
Photo 2/14   |   Evolution Of Diesel Performance Tuning
Until recently, ECM tuning was limited to people who could hack into and reprogram the stock engine and transmission-control modules, which was a very select group. Most of the sources for “flashing” the computers were also pretty tight-lipped on exactly what they were doing with timing, injector pulsewidth, or pretty much anything else associated with managing engine functions.
EFILive, a New Zealand-based company that started in the gasoline-engine market, saw the potential of the Duramax and released a new type of software that presented users with access to virtually all of an ECM’s tables and the ability to change values up or down. With the program, users could see everything from the thermostat’s set temperature to how much the engine de-fuels between shifts. While it took a few years for folks to fully grasp the idea of tuning their own trucks, eventually, small shops that could take the time to build and tailor a tune specifically for a customer's truck started becoming more prevalent.
Dodge offered common rail–injected 5.9L powerplants in 2003, while Ford stuck with its HUEI-fueled 6.0L Power Stroke until 2008, when the 6.4L Power Stroke was introduced. By that time, all three of the Big Three’s diesels could be tuned with a laptop and software such as H&S Performance’s MCC, EFILive, and even Smarty, which had a program called UDC. The ability to delve deep into a processor and manipulate its settings opened the door to using bigger injectors to make power while still burning clean, controlling turbos to stay in the sweet spot of their boost curves, and even improving transmissions’ shift timing and firmness.
Photo 3/14   |   Although the real revolution in the computer-based diesel tuning would come in 2001, with the introduction of GM’s 6.6L Duramax LB7 engine, the process actually started to evolve in the late ’90s. Trucks like this Dodge Ram (fueled by a VP44 injection pump) could be hopped-up with a simple "plug-and-play" handheld programmer, which enabled users to change timing and fuel curves by just pressing a few buttons.
All this hoopla came at a price, however: a serious crackdown by one of the most feared agencies in the automotive industry, the Environmental Protection Agency.
The EPA has been around since 1970, and there's absolutely no question the agency has helped improve the air we breathe, especially in big cities. Unfortunately, however, between 2010 and 2013, the EPA turned its focus to diesel tuners, who were increasing power levels by adding fuel, a practice that creates smoke and particulate matter that’s emitted into the atmosphere. Unlike gasoline-powered vehicles, which produce much greater tailpipe emissions without it being visible, diesels literally left a black mark on the industry, as removing diesel particulate filters and emissions-off tuning became more and more popular.
The repercussions of these practices between 2013 and 2019 have been severe. H&S Performance is probably the most recognized for receiving a harsh punishment of fines and sanctions levied by the EPA, which forced its closure in 2013. More recently, Edge Products was monetarily penalized, as was Spartan Diesel Technologies. As of 2019, Adrenaline Truck Performance has also stopped tuning.
"I'm not surprised," says one company owner who has had some interaction with the EPA. "It's all a money grab. People think they're getting away with it, but really the EPA and CARB are just waiting until the companies get big enough where they can sue them for millions.”
“I can say that I have nearly $500,000 in cash set aside for this type of situation, because we all know that if we’re doing it (tuning illegally), the EPA is coming," notes another tuner who declined an official interview.
Photo 4/14   |   H&S Performance was a leader in diesel ECM calibrating for many years, with its Mini Maxx monitors that allowed an easy defeat of stock emissions systems. Eventually, the EPA ordered the company to stop producing the products, which ultimately led to the closure of H&S.
With regard to today’s buzz term, “clean tuning,” let’s be clear: Without the endorsement of the California Air Resources Board (by way of an Executive Order number), even so-called "clean"/smoke-free ECM calibrations are still technically illegal, despite the good they do for performance and the environment. The key to the diesel hobby’s longevity and ability to sustain truly lies on product manufacturers’ pursuit of CARB certification and enthusiasts’ willingness to comply with the regulations imposed on diesels.
For this report, we feel it is important to give you the insights of some of the diesel scene’s biggest names, including a few very reputable tuners who requested to remain anonymous. Since one of our mystery men was probably the most honest, we'll start with him first.
"It's not that tuning is really that difficult, it just takes time," he says. "The factory engineers aren't idiots; they know people will be hard on diesels, so there are safeguards on everything from fuel to boost to brake-torquing the truck—even engine temperature and fuel level. Missing just one parameter when creating a tune typically makes the difference between an engine running well and making the power it should. Also, a lot of people don't understand there are fundamental limitations to diesels, and if you actually do try and get away with setting the ignition timing at 40 degrees, you're probably going to crack a piston,” he states.
“Given the profit margin in tuning, many people who shouldn't be tuning are having a go at it. A lot of people won't admit it, but I'd estimate a full 80 to 90 percent of tuning still involves deletes, whether it's a DPF, EGR system, or other emissions-related component,” he says.
Photo 5/14   |   Part of the allure of electronic tuning is that power levels can be changed with keystrokes on a handheld programmer or laptop computer. Very popular in late-model Ford Power Stroke, Duramax, and Cummins-powered trucks, these calibrations can range anywhere from completely stock to wild.
After receiving this warning shot, which we hope readers will think about before tuning a diesel pickup (as an owner or an actual calibrator), we went on to speak with Vivian Machado from Quick Tricks Automotive, Edge Products’ Marketing Manager Jared Venz, and PPEI’s Kory Willis regarding their thoughts about “coming clean.”
Vivian, who creates calibration strictly for DPF and emissions-on vehicles, advises "there are literally thousands of parameters in an ECM that can be manipulated, so you have to be careful. Tuning is basically attempting to successfully achieve the best balance of increased airflow and fuel that is delivered to an engine," she continues. "We have seen very good performance and fuel-economy gains with a newer 6.7L Ford while leaving the truck’s emissions hardware and electronics intact," she adds.
Jared echoes Vivian's sentiment: "Years ago, the EPA and CARB came to us and said we needed to stop offering delete tunes, and we voluntarily elected to shut down that segment of our business. The decision proved to be a good one, as it helped us develop products such as the Insight CTS and CTS2 monitors, and eventually return to ECM tuning with CARB-legal calibrations.”
It’s not all easy come for that CARB E.O., however.
"It can take anywhere from two months to a year to certify a product, but when it passes and receives a CARB E.O. number, we know that tune is approved for use anywhere in the U.S. We now have our own emissions-test equipment that helps us validate a product in-house before presenting it for certification," Jared says. "We’re proving that clean—and legal—tuning can be accomplished without having to be conservative about power gains. Our tuning for 6.6L Duramax LML engines adds nearly 130 hp.”
Photo 6/14   |   There are several different platforms used to create custom tunes. While EFILive is probably the most well-known software, companies such as HP Tuners, PPEI, Calibrated Solutions, and SCT offer programmers that also support custom tuning.
We believe that with this type of power being possible legally, there's still room for growth. We have found that modern diesel engines can typically run at 17:1 air/fuel ratio, and calibration will help make as much as 200 to 250 additional hp through enriching the air/fuel mixture to 14:1—which is well within the parameter for not emitting heavy smoke. With the addition of larger injectors and/or turbochargers, newer trucks are capable of making 500 to 550 hp.
There also are some companies that specialize in cloud/Internet-based diesel tuning.
PPEI's Kory Willis is one of the few tuners who supplies off-road-only ECM calibrations that is willing to go “on the record” for this report. "Right now, most tuners are pretending like the EPA doesn't exist, and diesel enthusiasts are pretending like the EPA doesn't exist, and that's simply not the case," he says. "There are literally thousands of diesel and gas vehicles out there that are street-driven yet still participate in closed-course competition events. We need to come to terms with laws that make sense and rules for these types of vehicles. We're actively working with the EPA to explore these types of options."
So, what does the future hold for diesel tuning? While we don’t know when it will happen, we believe ECM calibrating may branch into two separate directions. Brand-new trucks (once the most popular engines to tune) would rarely be modified thanks to their increasing stock horsepower and torque output and the manufacturers’ efforts to thwart manipulating ECMs by encrypting processors with multiple security/anti-tamper codes.
Photo 7/14   |   Products like the EZ Lynk Autoagent are thought to be the future of tuning. The device eliminates emailing calibrations back and forth (between tuners and technicians, owners, and such), or waiting for ECMs to be modified. This cloud-based tuning and data-logging software allows users to access files straight from the Internet.
ECM swaps (exchanging a stock processor for a modified ECM with custom tuning) are currently the only viable option for supporting the very big power gains that are brought about by extensive engine modifications. However, ironically, the $3,000 to $5,000 price for this type of upgrade (along with the major OEM powertrain warranty implications) makes a lot of new-truck owners hesitant to do it.
We think tuning activity for older trucks, on the other hand, will increase, especially as their emissions-related parts start to fail. “When the option comes to spending thousands of dollars (DPFs are nearly $2,000 alone for a 6.7L Cummins engine) to replace failing parts, most customers will just opt for a delete tune and be done with it," notes one anonymous calibrator. We think more small shops will specialize in offering tunes that are cloud-based, in an effort to avoid official reprimand. Off-road–only tuning will also become more popular, as diesels participate in other forms of motorsports, and events such as the Ultimate Callout Challenge become more popular.
While there is no certainty about any of this right now, there is one thing we are sure about: Diesel tuning will continue to be one of the most exciting, misunderstood, and maligned markets for many years to come.
Photo 8/14   |   Scheid Diesel Service is best known for its 3,000hp sled-pulling trucks. What you probably don’t know is the company has a DPF cleaning machine that can handle soot buildup in everything from pickups to big rigs. "They're (DPFs) on everything now, so it's a direction we knew we'd have to take," Dan Scheid says.
Photo 9/14   |   To see how an actual tune is modified, we took a look at the main injection-pulse table for the ECM of an '01 GM pickup powered by a 6.6L Duramax LB7 engine. Note how the stock pulsewidth actually drops as rail pressure rises.
Photo 10/14   |   This modified table (blue area) shows a big increase in pulsewidth, which equates to a gain of several-hundred horsepower. The top-left is the modified area (high rail pressure, full throttle), and the rest of the table remains fairly stock to preserve part-throttle driveability.
Photo 11/14   |   Just because one parameter is changed, doesn't mean the ECM won't override it elsewhere. This table limits the engine’s torque to prevent the transmission from being damaged. Even if fuel is added or power is increased through timing, the processor will still limit maximum torque. To build a comprehensive tune, there are literally dozens of tables like this that must be balanced in order for everything to function correctly.
Photo 12/14   |   It's important to verify how a tune performs after it's installed. Too often we hear "that truck runs hard," but unless you have some kind of verification from a dragstrip or chassis dyno, you can't be sure. "You don't know where you need to go until you know where you've been," says one anonymous tuner.
Photo 13/14   |   This is Bosch Motorsports’ stand-alone ECM, a processor capable of managing the functions of virtually any diesel engine. However, because of its hefty price tag, these units are more commonly used in all-out competition vehicles.

Executive Order

In the diesel-tuning space, there are companies that invest a significant amount of manpower and financial capital to develop diesel-performance accessories, including tuning hardware and software. Edge Products and its sister brands (DiabloSport and Superchips) offer diesel products that are in compliance with federal emissions regulations and/or qualified to begin the application process for California Air Resources Board (CARB) certification. “While technology, engine capabilities, and emissions requirements are always subject to change, we carefully evaluate every tunable table parameter that can be engineered for improvement, good driveable horsepower, and torque gains while staying 50-state legal,” Edge’s Marketing Manager, Jared Venz, says.
“The Executive Order (E.O.) numbers we have received are the most comprehensive and detailed of their kind when it comes to the space our company operates in today,” says Powerteq (Edge Products’ parent company) Division President Dave Martinez.
Why is a CARB E.O. important? The short answer is because the number confirms that a product installed on a vehicle has been tested in an authorized facility and meets the regulatory body’s standards for emissions. In almost all instances, this confirmation is required for motor vehicles that are registered and inspected in California or other areas that have adopted CARB’s standards. Inability to produce an E.O. during an inspection can result in fines being assessed and a vehicle failing inspection.
Photo 14/14   |   This photo details results of the CARB emissions tests that were performed to evaluate Edge Products’ 6.6L Duramax LML calibration. The gas levels measured include THC (Total Hydrocarbons), CO (Carbon Monoxide), NOx, CO2 (Carbon Dioxide), NMHC (Non-Methane Hydrocarbons), and PM (Particulate Matter).

Sources

Edge Products
Ogden, UT 84404
801-476-3343
www.edgeproducts.com
Scheid Diesel
Terre Haute, IN 47805
816-466-7202
www.scheiddiesel.com
HP Tuners
Buffalo Grove, IL 60089
www.hptuners.com
SCT
Longwood, FL 32750
407-774-2447
www.sctflash.com
EZ Lynk
ezlynk.com
PPEI
337-990-4840
ppei.com
Quick Tricks Automotive
305-328-8778
quicktricksauto.com
Environmental Protection Agency
epa.gov
Bosch Motorsport
bosch-motorsport.com

POPULAR TRUCKS

MOST POPULAR

Subscribe Today and Save up to 83%!

Subscribe Truck Trend Magazine

Subscribe to:

Truck Trend
Magazine

PRINT DIGITAL
Subscribe Diesel Power Magazine

Subscribe to:

Diesel Power
Magazine

PRINT DIGITAL
Subscribe Truckin Magazine

Subscribe to:

Truckin
Magazine

PRINT DIGITAL
SUBSCRIBE TO A MAGAZINE
CLOSE X
BUYER'S GUIDE
SEE THE ALL NEW
NEWS, REVIEWS & SPECS