How Ayrton Senna's Penske IndyCar test unfolded

Fittipaldi started the day by driving the '92 Penske. “It was cold and the track was slippery," Beresford said. "Emmo spun on cold tyres, but eventually found the car pretty well balanced and just lacking overall grip.

"He came in, we changed tyres, and adjusted the brake balance a bit more towards the rear. He completed a 12-lap run and a 13-lap run, setting a best time of 49.7 seconds twice."

Senna’s turn

After a short break, Senna slid into the narrow cockpit of the Penske Indy car.

Ayrton Senna, Penske Chevrolet PC22

Ayrton Senna, Penske Chevrolet PC22

“Normally, Formula 1 drivers get on the pace immediately," said Beresford. "Ayrton started doing some pretty slow laps initially, and that was a surprise.

"This car had a sequential gearbox and Senna had to get used to manipulating a gear shifter again. On occasion, he would lose his way through the gears. He would stop the car completely, select first gear and then go again.

Senna had to get used to the characteristics of a turbo car. After completing 14 laps, he came back into the pits with a best lap of 49.5 seconds.

“He told me the engine was very drivable, and found the car pretty heavy - not as nimble as a much lighter F1 car - and added he did not know the revs he was pulling because the engine sounded so different," added Beresford.

"Firebird has one moderately quick corner, and Senna was just starting to push the car through that corner. He could feel the weight of the car; he did not want to push it to the limit. It was not the place, nor the time, to do it.

"He wanted to see the sensitivity of the car, so we put softer springs at the rear, disconnected the rear anti-roll bar, and added 20 gallons of methanol."

Ayrton Senna, Penske Chevrolet PC22

Ayrton Senna, Penske Chevrolet PC22

"Amazingly quick"

The three-time World Champion did another 10-lap run on the same set of tyres, and set a best time in 49.09 seconds.

“He came back into the pits and said 'Thank you very much, I've learned what I need to know.' He got out of the car and that was that,” Beresford continued.

“Senna did not disappoint me at any level. He was just amazingly quick. Emmo’s best lap was a 49.7 compared to Senna's 49.09.

"At the end of the day, Emerson did a 48.5 in the new Penske, and that was just 0.6s quicker than Senna. That was very good considering Ayrton was driving a year-old car on old tyres.

"To me, that indicated just how extraordinarily quickly he was able to adapt himself and approach competitive times."

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