Acceleration is one of the forces that make life interesting. Think about it. What are the most exciting rides at the amusement park? The rides with sudden changes in acceleration! Examples include the roller coasters that slowly climb to the top, and then suddenly drop out from beneath you, accelerating all the way to the bottom, or the rides with the big outward turns where the centrifugal acceleration is greatest. Even attractions that put you in a room with a video screen, and then shake you to bits (like Universal Studio’s Star Wars ride or the NASCAR simulator), are based upon acceleration rather than speed; the room doesn’t go anywhere. On most of these rides the top speed that you reach is slower than you drive when going to the supermarket. The ride-makers use acceleration to provide the thrills.

Automakers have known about this for some time. That’s why engines keep getting more and more powerful. We can’t go any faster than we do already, but we can get going fast quicker! Ten years ago the average SUV had an engine that produced 175 horsepower. Now many SUV’s have 300 horsepower engines. The unfortunate down side of having lots of acceleration on tap, is that the overall fuel economy generally decreases.

The automakers are battling high gas prices and political pressure to improve fuel economy. But when they make a very fuel efficient vehicle few people buy it. When they produce a powerful vehicle it sells to the masses.

This is where the hybrid vehicle is coming to the rescue of the automakers. A hybrid vehicle combines a conventional gasoline engine with an electric motor. This combination was originally put together to improve fuel economy. But then the automakers realized another benefit – more acceleration with smaller engines.

Gasoline engines need to be running at high rpm’s to produce their maximum torque, or acceleration. Right off of the stop line they are not yet at maximum torque. But electric motors have their maximum torque right from the start. As electric motors reach their higher rpm range their available torque begins to fall off. Combine the two and you have a greater range of available torque or acceleration.

The first hybrid vehicles were little economy cars with very small gasoline engines, great fuel economy, but sluggish performance. The original objective was maximum fuel economy. But that only appeals to a small segment of the population. Acceleration sells better than mpg. But now hybrid vehicles have moderate size gasoline engines. This is because the automakers want to provide the thrilling acceleration that sells cars, with the fuel saving benefits of a moderate, rather than a big, gasoline engine.

I drove a hybrid Toyota Camry recently. When I used a moderate throttle from the stop line the car was a little sluggish. The computer was trying to provide maximum fuel economy. But when I asked for full throttle from a stop the computer used the electric motor, gasoline engine, and the continuously variable transmission to provide maximum acceleration. It was every bit as quick as a V6 Camry.

Lexus has said that 100% of their vehicles will use hybrid power trains by 2010. The people working at Lexus are pretty smart. They will have snappy cars and SUV’s that compete with the other expensive automobiles with large powerful engines, but will have better fuel economy because their hybrid engines aren’t quite so big.

Brian Klaubert has written for the Neighborhood News for five years, and owns Christian Brothers Automotive – Hamilton Mill on Braselton Hwy in Dacula. They have won “Best Mechanic” in the 2007 “Best of Gwinnett” award in Gwinnett Magazine.