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EFI telemetry fine-tuning learning curve into exact science

April 08, 2012, Mark Aumann,

EFI telemetry fine-tuning first-year learning curve into more of an exact science

Just six weeks after replacing the tried and true carburetor, electronic fuel injection already has proven to be a game-changing technology in NASCAR -- both in a good and bad way.

Just about everyone knows about Tony Stewart's balky circuit breaker at Phoenix, and the failed fuel pumps suffered by Penske's two drivers at Las Vegas. Those teething problems were surprising but not unexpected.

"You can now diagnose the failure rather than presume something. It does make the end product better."



"It'll probably be this summer before we fully integrate the culture of NASCAR with this new science. But it's a great opportunity."


Hendrick Motorsports director of engine operations Jeff Andrews has a different story to tell. After the seven cars with Hendrick engines practiced at Martinsville Speedway last weekend, team engineers took the data to the shop in Concord, N.C. They hooked up a test engine on the dyno, and using telemetry collected hours before, were able to make specific changes to the computer program that controls the EFI.

"We actually came back here to our shop on Saturday and did some running with some of the data we gathered from Martinsville," Andrews said. "Then we did some more adjustments to the calibration and mapping for the race on Sunday."

How well did it work? Behind a dominant performance by Jeff Gordon and Jimmie Johnson, Hendrick cars led 455 laps -- and even though the team didn't land Rick Hendrick that elusive 200th win, the engine department still had reason to celebrate with Ryan Newman at race's end.

As the seven-post shaker rig has revolutionized chassis setups, the EFI telemetry that's available every time a car returns to the garage area isn't just providing an impact on engine design and tuning, but helping drivers "see" what their teammates are doing behind the wheel.

"The drivers can look at each other's throttle traces and brake pressures, and really compare driving styles," Andrews said. "Before, it was verbal conversation -- 'I'm doing this here, this is where I'm getting back on the throttle and this is how I use the brake.' Now there's data. You're able to sit down and look at that between practice sessions."

And the biggest fear drivers had with the switch -- whether they'd feel the difference in throttle response between carburetors and EFI -- has been largely mitigated, according to Howard Comstock, manager of engineering for Chrysler Group's Street and Racing Technology Motorsports division.

"A lot of people were worried about drivability with EFI and we've seen none of that," Comstock said. "That's not surprising. We had a pretty good idea that we had it figured out, that you'd make these things drive.

"If you don't bring it up to the drivers, they don't bring it up to you. And that's all good news for us."

For the most part, crew chiefs also have been able to make a seamless transition. Darian Grubb, crew chief for Denny Hamlin's No. 11 Toyota, said there haven't been any surprises.

"It's more just a learning curve of a whole new system," Grubb said. "We've been working with carburetors for over 60 years. Just having to learn all the new systems and everything being computerized and just making sure everyone is up to speed with the technology."

For him, it's "a new thing to pay attention to every day."

Electronic fuel injection has been on Doug Yates' mind for months. As head engine builder for Roush Yates Engines -- the main supplier for Ford's Cup engine program -- Yates has been at the forefront of the EFI transition.

For a guy who has been tinkering with engines since his father, Robert, let him work in the race shop as a teenager, Doug Yates understood the intricacies of the carburetor perhaps better than anyone else in the garage. But he can barely contain his excitement when the subject of EFI gets brought up.

"It's an exciting time to be an engine builder," Yates said. "With all the information we have today that we've never had before -- and what we can do with that information -- has continued to make the engines perform better at the track. And also understanding the limits of the engines."

Just like tuning a piano, tuning a race engine takes a trained ear. For an engine tuner, the switch from carburetion to electronic fuel injection is akin to a recording studio making the leap from analog to digital.

That's not to infer that EFI is more "sterile" or requires less artistic ability to master. Yates said it's just a different way to achieve a similar solution.

"The whole weekend goes differently now," Yates said. "With carburetors and distributors, you'd look at the spark plugs and listen to the engines, think about things and make your decisions. Now, you have data you can look at from here until tomorrow. And you're building that database."

For decades, engine building has been a matter of trial and error. Design a part, machine it, put it on the car and see if it can withstand the stresses of 500 miles at 180 mph. If it does, refine it. If it doesn't, start over.

But for the most part, there were very few ways to measure exactly why parts and pieces break. Until now.

"Especially when you build multiple engines for several teams, you kind of tend to [gravitate to] the worst condition," Yates said. "If one person has an engine failure, you'd go to work and protect for that.

"Now you have the information and can see that every engine doesn't experience the same operating conditions, operating temperatures. So now you can make a better engine down the road because you understand better what the operating conditions are. The information will make us better."

Andrews already has seen the benefits. You can spend unlimited hours --and dollars -- on computer-aided design, in the dyno room and at testing, and at the end of the day, still wonder if everything will work correctly.

That's why being on the track in racing trim -- and being able to collect real-time data -- is so critical. It provides that little extra peace of mind about engine function and reliability.

EFI technology

Welcome to the computer age, and that means engine builders are trading in their wrenches and benches for laptops and software.

"The conditions inside of the car and under the hood -- and all of the things that go on during the weekend, whether it be restarts or pit stops, temperatures and brief overheating periods -- these are all things now the engine management system reacts to," Andrews said. "Once you start throwing seven [engines] out there every weekend, your sample rate goes up dramatically. And so does the likelihood of what we like to refer around here as 'new challenges.' "

Yes, Kasey Kahne had engine issues at Martinsville, but Andrews was quick to point out that even though the team still is investigating the reasons why, EFI was not to blame.

If anything, the telemetry helps determine the 'smoking gun,' said Ron Sperry, components design engineer for GM Racing Group. Data acquisition helped figured out the underlying cause of Jeff Gordon's problems in the Daytona 500.

"In the Jeff Gordon failure, we could see coolant loss," Sperry said. "Now, we couldn't see it immediately, but with the telemetry after the fact, we could go back and look at the historical data and see that he did have a coolant loss and it led to a piston failure later in the race.

"You can now diagnose the failure rather than presume something. It does make the end product better. And now piston temperatures are more consistent. You now have consistency from cylinder one to cylinder eight."

Now that EFI has been race-tested at every configuration -- with the notable exception of a road course -- Andrews can't wait to measure the progress his group has made.

"We have a list of feedback and areas of improvement from Las Vegas that we've addressed and are anxious to get to Texas to try those out," Andrews said.

Andrews isn't the only one. Toyota Racing Development president Lee White has been an adamant supporter of electronic fuel injection since the topic first came up in conversation. With 180 employees in California supporting TRD's program, he envisions a time not too far in the future where EFI becomes "routine."

For now, it's more a matter of getting man and machine working together.

Doug Yates always has had a good ear when it comes to engines, but now he's building a database of invaluable information. (Getty Images)

"Everyone is still learning to mesh that five inches between the driver's ears with what's coming out of their laptops," White said. "It'll probably be this summer before we fully integrate the culture of NASCAR with this new science. But it's a great opportunity."