Sentence:  Seppi started the engine, then shifted first gear and sped away into second, then third and fourth gear. Frank heard the roar of the Porsche's engine further down the <WSD>straight</WSD> and the back short straight. He held a stopwatch in his hand, waiting for him to come up into the <WSD>straight</WSD> from the hairpin curve. 
Meaning of the word marked with <WSD> tags:  Something that is not crooked or bent such as a part of a road or track.