Note the cool air brake on the tail of Parnelli's #40 STP car, visible in operation at around 12:41 of this video (and also at 27:35, where the announcers mention it). It deploys upward to provide aerodynamic drag for braking.
Pay attention also at 25:20, when Parnelli spins the car after going low on the apron to avoid a slower car.
Other race highlights:
At 2:44, Dan Gurney is being interviewed, and predicts that the turbine car might have gearbox failure (I think this is called "foreshadowing").
At 26:40, Mario Andretti loses a wheel.
At 28:00, the STP team has a bungled pit stop. Jones pulls off before the fuel hose is disconnected from his car, and almost runs over Granatelli's foot.
At 45:30, eventual winner A. J. Foyt comes close to being collected up in a last lap wreck.
Perhaps my favourite part of the video, though, is the interview with Graham Hill, which begins around 2:12. Many drivers were resentful of the turbine car's speed. But Hill had a different take:
"I don't think it's unfair at all! I think it's bloody clever, and full marks to Granatelli for doing it. I man, it was a hell of a gamble, and it's paid off. I think he deserves every credit. I'm only sorry thta I didn't think of it first!"