# Masaki Jyonai

Masaki Jyonai (城内 政樹, Jōnai Masaki, born 9 September 1962) is a Japanese racing driver and businessman.

## Racing career

Jyonai started karting in 1988; he is noted for his extensive experience in kart racing, having won numerous karting championships. He moved to car racing in 1993, racing in the Suzuka 1000 km in the Proto 2 class; he won on his debut.
Jyonai began competing in Super GT in 1997 with the SigmaTec Racing Team. As of 2023, he has won two races; his best finish in the championship is 5th, achieved in his first year in the series. Outside of racing, Jyonai is the CEO and President of Marusho Co. Ltd., a company involved in the lighting, security and construction sectors. He is also a lecturer at the karting classes of Honda Racing School Suzuka as well as a color commentator for various television programs.
He occasionally competes using the pseudonym Guts Jyonai (Guts城内, Gattsu Jōnai); Jyonai says he took the name from comedian Guts Ishimatsu. In more recent years he has reverted to using his real name.

## Racing record
### Complete Super GT results

(key) (Races in bold indicate pole position) (Races in italics indicate fastest lap)
| Year | Team | Car | Class | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | DC | Points |
| 1997 | SigmaTec Racing Team | Porsche 911 GT2 | GT300 | SUZ | FUJ 6 | SEN 7 | FUJ 6 | MIN 2 | SUG 1 | | | | 5th | 51 |
| 1998 | SigmaTec Racing Team | Porsche 911 GT2 | GT300 | SUZ Ret | FUJ C | SEN 9 | FUJ 4 | MOT | MIN | SUG 16 | | | 21st | 12 |
| 1999 | SigmaTec Racing Team | Porsche 911 GT2 | GT300 | SUZ DSQ | FUJ 3 | SUG 6 | MIN 11 | FUJ 19 | TAI Ret | MOT DNS | | | 15th | 18 |
| 2000 | SigmaTec Racing Team | Porsche 911 GT2 | GT300 | MOT | FUJ 12 | SUG 4 | FUJ Ret | TAI 4 | MIN 7 | SUZ 5 | | | 11th | 32 |
| 2001 | SigmaTec Racing Team | Toyota MR-S | GT300 | TAI Ret | FUJ | SUG Ret | FUJ Ret | MOT Ret | SUZ 11 | MIN 1 | | | 14th | 20 |
| 2002 | SigmaTec Racing Team | Toyota MR-S | GT300 | TAI 14 | FUJ 2 | SUG Ret | SEP | FUJ Ret | MOT 10 | MIN 13 | SUZ 6 | | 15th | 24 |
| 2003 | SigmaTec Racing Team | Toyota MR-S | GT300 | TAI 4 | FUJ 7 | SUG Ret | FUJ 18 | FUJ | MOT | AUT | SUZ | | 16th | 16 |
| 2003 | SigmaTec Racing Team | Toyota Celica | GT300 | TAI | FUJ | SUG | FUJ | FUJ Ret | MOT | AUT | SUZ | | 16th | 16 |
| 2004 | Team Gaikokuya | Porsche 911 GT3-R | GT300 | TAI 13 | SUG 21 | SEP | TOK | MOT | AUT | SUZ | | | 20th | 2 |
| 2004 | Arktech Motorsports | Porsche 911 GT3 | GT300 | TAI | SUG | SEP | TOK 20 | MOT 9 | AUT | SUZ 17 | | | 20th | 2 |
| 2005 | Team LeyJun | Porsche 968 GT4 | GT300 | OKA Ret | FUJ Ret | SEP NC | SUG 16 | MOT DSQ | FUJ 14 | AUT Ret | SUZ Ret | | NC | 0 |
| 2006 | Team LeyJun | Porsche 911 GT3 | GT300 | SUZ Ret | OKA | FUJ 16 | SEP | SUG | SUZ 15 | MOT 23 | AUT | FUJ 25 | 37th | 1 |
| 2007 | A&S Racing | Mosler MT900R | GT300 | SUZ Ret | OKA 23 | FUJ Ret | SEP | SUG | SUZ | MOT | AUT | FUJ | NC | 0 |
| 2007 | Arktech Motorsports | Porsche Boxster | GT300 | SUZ | OKA | FUJ | SEP | SUG 17 | SUZ Ret | MOT | AUT 17 | FUJ 19 | NC | 0 |
| 2008 | Arktech Motorsports | Porsche Boxster | GT300 | SUZ 15 | OKA | FUJ | SEP | SUG | SUZ | MOT | AUT | FUJ | NC | 0 |
| 2008 | Tomei Sports | Porsche 911 GT3 | GT300 | SUZ | OKA | FUJ | SEP | SUG | SUZ 16 | MOT | AUT 16 | FUJ 15 | NC | 0 |
| 2010 | R'Qs Motorsports | Vemac RD350R | GT300 | SUZ | OKA | FUJ | SEP | SUG | SUZ 13 | FUJ C | MOT 18 | | NC | 0 |
| 2011 | R'Qs Motorsports | Vemac RD350R | GT300 | OKA 13 | FUJ 13 | SEP 16 | SUG Ret | SUZ 19 | FUJ | AUT 14 | MOT | | NC | 0 |
| 2012 | R'Qs Motorsports | Vemac RD350R | GT300 | OKA 16 | FUJ 12 | SEP 18 | SUG DNQ | SUZ 12 | FUJ 16 | AUT 18 | MOT | | NC | 0 |
| 2013 | R'Qs Motorsports | Mercedes-Benz SLS AMG GT3 | GT300 | OKA Ret | FUJ 13 | SEP Ret | SUG 19 | SUZ 12 | FUJ 17 | FSW | AUT 14 | MOT 16 | NC | 0 |
| 2014 | R'Qs Motorsports | Mercedes-Benz SLS AMG GT3 | GT300 | OKA | FUJ | AUT | SUG | FUJ 11 | SUZ 15 | CHA 9 | MOT 14 | | 35th | 2 |
| 2015 | R'Qs Motorsports | Mercedes-Benz SLS AMG GT3 | GT300 | OKA DNS | FUJ | CHA 15 | FUJ 10 | SUZ 16 | SUG 10 | AUT 22 | MOT 24 | | 32nd | 2 |
| 2016 | R'Qs Motorsports | Mercedes-Benz SLS AMG GT3 | GT300 | OKA 19 | FUJ Ret | SUG 20 | FUJ Ret | SUZ 23 | CHA 18 | MOT 21 | MOT 21 | | NC | 0 |
| 2017 | R'Qs Motorsports | Mercedes-Benz SLS AMG GT3 | GT300 | OKA 24 | FUJ 23 | AUT 26 | SUG | FUJ 26 | SUZ 21 | CHA | MOT 25 | | NC | 0 |
| 2018 | R'Qs Motorsports | Mercedes-AMG GT3 | GT300 | OKA 19 | FUJ 25 | SUZ 25 | CHA | FUJ 21 | SUG DNQ | AUT 25 | MOT 28 | | NC | 0 |
| 2019 | R'Qs Motorsports | Mercedes-AMG GT3 | GT300 | OKA 17 | FUJ 20 | SUZ 26 | CHA | FUJ 23 | AUT Ret | SUG | MOT 26 | | NC | 0 |
| 2020 | R'Qs Motorsports | Mercedes-AMG GT3 | GT300 | FUJ 24 | FUJ 28 | SUZ 23 | MOT Ret | FUJ | SUZ 26 | MOT 28 | FUJ 27 | | NC | 0 |
| 2021 | R'Qs Motorsports | Mercedes-AMG GT3 EVO 2020 | GT300 | OKA 20 | FUJ Ret | SUZ 28 | MOT 21 | SUG | AUT Ret | MOT | FUJ | | NC | 0 |
| 2022 | R'Qs Motorsports | Mercedes-AMG GT3 EVO 2020 | GT300 | OKA 25 | FUJ Ret | SUZ | FUJ 20 | SUZ 21 | SUG 24 | AUT 24 | MOT 22 | | NC | 0 |
| 2023 | R'Qs Motorsports | Mercedes-AMG GT3 EVO 2020 | GT300 | OKA 20 | FUJ 21 | SUZ 26 | FUJ 24 | SUZ 20 | SUG 16 | AUT 21 | MOT 22 | | NC | 0 |
* Season still in progress.