Impul driver Hirakawa was again one of the main protagonists of the 2022 season, scoring two wins in the first half of the season at Fuji and Autopolis.
But a series of difficult races from poor grid slots after that blunted his charge, with his bid to overhaul Nojiri for a first Super Formula crown finally coming to an end in the first race of last weekend's Suzuka double-header.
Looking back on a campaign that had started with so much promise, Hirakawa said that Impul's failure to get on top of its qualifying woes ultimately proved fatal to his title ambitions, having only managed one top-three grid slot in 2022.
By contrast, Nojiri scored six poles from 10 races, only qualifying outside the top three on two occasions all year.
"The season started well, we won the first race and we were second in the second race," Hirakawa told Motorsport.com. "But Nojiri’s qualifying average was 2.2... this is crazy. This is the difference between us.
"He could always do his own race from the front row, so it’s natural so he has that performance. For me, because we struggled in qualifying, I had to take more risks, sometimes it went well and sometimes not.
"This sums up the season well, and it’s why he won the championship by such a big gap. Definitely qualifying was the key."
Super Formula's top qualifiers in 2022:
| Pos. | Driver | Team/Engine | Avg. grid slot | Bonus points |
|---|---|---|---|---|
| 1 |
 Tomoki Nojiri |
Mugen/Honda | 2.2 | 20 |
| 2 |
 Sacha Fenestraz |
Kondo/Toyota | 5.8 | 7 |
| 3 |
Ritomo Miyata |
TOM'S/Toyota | 6.8 | 8 |
| 4 |
Tadasuke Makino |
Dandelion/Honda | 7 | 1 |
| 5 |
Sho Tsuboi |
Inging/Toyota | 8.8 | 2 |
Hirakawa went into the final race of the season tied for second on points with fellow Toyota engine user Sacha Fenestraz, but was beaten in a straight fight by the departing Kondo Racing driver.
While admitting that third overall was a fair reflection of his performance, Hirakawa revealed that both Impul cars were struggling with a mysterious lack of top speed which allowed Fenestraz to pass at Turn 1 on lap 5 of 31.
Analysis of their battle on the 'SF Go' app shows Fenestraz recording a top speed of 290km/h (180.2mph) versus 285km/h (177.1mph) for Hirakawa, with both drivers using the Overtake System at the time.
"Our car, also the #19 [of teammate Yuhi Sekiguchi], struggled in the straight line," Hirakawa said. "That’s why Sacha was able to pass me and I struggled to pass [Sho] Tsuboi [who had a damaged floor from earlier contact].
Hirakawa added that he hopes the potential introduction of an upgraded car in Super Formula with new a new aero package aimed at creating closer racing could give Impul the impetus it needs to catch Nojiri in 2023.
"It’s not completely a reset, but maybe it can neutralise [Nojiri’s advantage] by changing the aero," he said. "I hope we can find something quickly, otherwise the title fight can be over quickly."
