Fuel injection, ECUs and the pressure of NASCAR racing

SAN FRANCISCO -- NASCAR this season embraced one of the most significant engine-performance changes in the past 50 years: It mandated fuel-injection, throwing over 50 years of carburetor use fondly remembered by engineers and mechanics.

It was a high-profile switch, and all eyes were on the teams this season to see how fuel injection would stand up to brutal race track environments. And no one was more in the center of that collective gaze than Freescale and McLaren Electronic Systems.

The two companies, which have worked together on automotive electronics designs since 2000, won the bid to supply the engine-control unit managing the new fuel-injection systems starting this season. The McLaren TAG-400N--designed specifically for NASCAR Sprint Cup Series cars--controls eight-cylinder race engines with Freescale Power Architecture MCUs at its core. Freescale's microcontroller evaluates data from sensors all over the engine, then determines the precise amount of fuel to be delivered to the engine's manifold—at about 1,000 times per second.



(Source: NASCAR.com)

It wasn't a huge jump for the pair--a version of the TAG-400 has been used by the Indy Racing League (IRL) since 2007--but NASCAR is big, and there was considerable pressure to perform. On top of that, NASCAR's biggest race every season is its first, the Daytona 500. If the ECUs fail during that race, it's a big black eye on Freescale, McLaren and other components vendors in the system.

"It (the change) was about competition on the track," said Steve Nelson director of marketing for the Americas at Freescale. "When you change the competition--introduce a new golf ball or whatever--changing that introduces risk. How is it going to work out?"