Technology countdown: Electronic fuel injection

April 23, 2013, Zack Albert,

EFI at cutting edge of NASCAR engine technology

Over the course of his 25-year career in NASCAR's highest levels, Jeff Burton has seen plenty of development in modern racing machinery. Body styles, aerodynamics, safety measures -- all evolved over the better part of two decades, but until recently, all those stock cars had a common thread: carburetors.

That changed at the start of the 2012 season. The advent of electronic fuel injection (EFI) in the NASCAR Sprint Cup Series tipped the scales toward a more advanced race car, changing the face of competition in NASCAR's premier series. In doing so, the engine technology gave a nod to the cars' street-legal counterparts, a potentially necessary move before more product relevance could be achieved with the 2013 debut of the sixth generation of Sprint Cup car.

"I do think the product is better when it's kept simple, but I believe we also kept it too simple for too long," Burton said of the carburetion era. "NASCAR always wanted it to be as simple as could be so that more teams could be competitive, and that's a good theory, but this is a different time. Today's young people, or even today's older people, are so much more tech-savvy that to be around carburetors is a bit ancient. So it's definitely a step in the right direction. These cars need to be more technologically advanced."

The purpose of carbureted engines vs. those with electronic fuel injection is the same, but the delivery method is much different. Where the carburetor used to be the hub for mixing fuel and air to power the engines, now the fuel is directly injected into the engine's intake runners mixing with air from a throttle body.

The improvement in efficiency is further enhanced by an electronic control unit (ECU) produced by business partners Freescale and McLaren, which maximizes performance and provides race teams and drivers with valuable data.

"The driver data is really neat to have," Burton said. "We talk a lot about how we drive and those kinds of things between teammates. What we've learned is that unless you can look at data, that conversation doesn't mean a whole lot. It's so much better just being able to go look at data.

All that's been real beneficial to all the drivers, I think, just to make every driver better. That's something we've never had before. It's just given us more insight into what's actually going on."

Team engineer and crew chiefs have benefited alike. The system has allowed teams to gather data and make pre-race adjustments -- weighing performance strength against fuel economy, for example -- that weren't possible with the old engine rules.

The new system was tested extensively by teams and manufacturers ahead of the full-scale rollout in 2012 on NASCAR's biggest stage -- the Daytona 500. With such a drastic change from a status quo that had been in place for decades, the anticipation -- combined with a side order of slight anxiety -- was palpable heading into season-opening Speedweeks events at Daytona International Speedway.

"When you do something like this where you're going to have 20 or 30 million people watching on television, 200,000-plus in attendance, and all of a sudden we're going to run it in every single car?" said Steve Nelson, director of marketing for Freescale, the official automotive semiconductor of NASCAR. "You can be sure that there was -- I'm not going to say consternation -- but we sure wanted it to go well, without question."

And it has, much in the way that quality referees or umpires aren't noticed in a well-officiated ballgame.

"We knew if we got to April or May (2012) and you were still talking about this system, it is not good," Nelson said. "We wanted to be a non-story; we wanted it to be about competition."

With few exceptions -- mainly hiccups in tuning and fuel pickup -- the new EFI system has remained out of the spotlight for negative reasons. In more than 40 races since the implementation of fuel injection, not one engine failure has been traced back to the ECU unit, Nelson notes, pointing out that Freescale will cross the 1 million miles mark without a breakdown sometime this fall.

At least partial credit for the reliability goes to the collaborative effort between teams and manufacturers, plus the opportunity for teams to test the EFI system at four tracks over the summer and fall of 2011.

"Really, it's been my impression through the years, the more time the team has to work on it, the better the product will be because they know how to use it and test it better than outside groups would," Burton said. "I think teams got it early enough to sort through some of the things that were issues and looking back, for as big of a change as it was, it wasn't that bad."

Business partners Freescale and McLaren have combined to produce an electronic control unit, pictured above, that provides race teams with valuable performance data.