The redesigned Honda Fit that will be rolled out in the United States in mid-2014 won’t feature an engine stop-start system, a technology that helps save fuel by shutting off the engine at stoplights. Part of the reason is that the lag between stop and start makes the vehicle slow off the line. According to Nobuhiko Shishido, a lead powertrain engineer for the new Fit, speed and power rule in the US, leaving those small cars with stop-start systems in the dust.
Shishido remarked at a recent Fit preview that stop-start engines "will lose at stoplights to V-6s," referring to the extra split second it takes to re-engage the engine when a stop-start vehicle prepares to roll again. The stop-start system automatically shifts the car into neutral to turn off the engine. Then when a driver lifts his foot off the brake pedal, the starter motor re-engages the engine and the drivetrain is shifted back into drive.
The process may take nearly a second, according to Kentaro Yokoo, chief engineer of the hybrid drivetrain in the Fit. But one second may seem like eternity for those seeking to accelerate right when the stoplight turns green. Hybrid vehicles typically use the stop-start system as it helps improve fuel economy. But since big and powerful electric motors do double duty to restart the engine, the startup does not register delays.
On the other hand, non-hybrids are fitted with starter motors, which are typically weak to propel the vehicles seamless, according to Yokoo. Although engineers could offset this by increasing the size of the starter motor, this translates to additional weight and cost. The start stop system proved to be popular outside North America and comes as standard on all versions of Honda's new Fit in Japan.