| 26.4.1998 | 4 h Paul Ricard | 30 | Mantara LM600 | Euser / Buurman / Vann | Marcos Racing International | T-car |
| 3.5.1998 | Belcar Spa SFD | 22 | Mantis | Molenaers / Neyens | Marcos Racing Team Belgium | 21st |
| 4.5.1998 | British GT Oulton Park | 36 | Mantara LM600 | McKenzie / Phillips | Driver | DNF |
| 4.5.1998 | British GT Oulton Park | 41 | Mantis | Morgan / Duerden | Ciceley Race Team | 15th |
| 4.5.1998 | British GT Oulton Park | 44 | Mantara LM500 | Wyatt / Ward | Forward GT Racing | DNS |
| 4.5.1998 | British GT Oulton Park | 77 | Mantara LM600 | Sands / Purvis | Millennium Motorsport | DNF |
| 10.5.1998 | FFSA GT Spa | 64 | Mantis Challenge | Howard Furr-Barton | Auto Vitesse | 18th/DNF |
| 10.5.1998 | SM GTR Mantorp Park | | Mantara LM500 | Erik Holmqvist | | DNA |
| 17.5.1998 | 500 km Silverstone | 70 | Mantara LM600 | Euser / Becker | Marcos Racing International | DNF |
| 17.5.1998 | 500 km Silverstone | 71 | Mantara LM600 | Ashley / Vann | Marcos Racing International | DNA |
| 23.5.1998 | 4 h Misano | 30 | Mantara LM600 | Euser / Buurman | Marcos Racing International | 4th |
| 23.5.1998 | 6 h Misano | 30 | Mantara LM600 | Euser / Buurman | Marcos Racing International | DNF |
| 23.5.1998 | 6 h Misano | 45 | Mantara LM600 | | Marcos | DNA |
| 23.5.1998 | 4 h Misano | 45 | Mantara LM600 | | Marcos | DNA |
| 24.5.1998 | British GT Croft | 36 | Mantara LM600 | McKenzie / Phillips | Driver | 17th |
| 24.5.1998 | British GT Croft | 44 | Mantara LM500 | Wyatt / Beckwith-Smith | Forward GT Racing | 16th |
| 24.5.1998 | British GT Croft | 77 | Mantara LM600 | Sands / Purvis | Millennium Motorsport | 13th |
| 14.6.1998 | Belcar Spa PT | 21 | Mantara LM500 | Smolders / Jacobs | Marcos Racing Team Belgium | 48th |
| 14.6.1998 | Belcar Spa PT | 22 | Mantis | Molenaers / Neyens | Marcos Racing Team Belgium | 17th |
| 14.6.1998 | British GT Snetterton | 36 | Mantara LM600 | McKenzie | Driver | 16th |
| 14.6.1998 | British GT Snetterton | 44 | Mantara LM500 | Beckwith-Smith / Ward | Forward GT Racing | DNS |
| 14.6.1998 | British GT Snetterton | 77 | Mantara LM600 | Sands / Purvis | Millennium Motorsport | 12th |
| 28.6.1998 | 500 km Hockenheim | 70 | Mantara LM600 | Becker / Euser / Vann | Marcos Racing International | DNF |
| 11.7.1998 | FFSA GT Dijon | 64 | Mantis Challenge | Howard Furr-Barton | Auto Vitesse | 17th/17th |
| 12.7.1998 | British GT Silverstone | 36 | Mantara LM600 | Keith McKenzie | Keith McKenzie | DNS |
| 12.7.1998 | British GT Silverstone | 41 | Mantis | Morgan / Jackson | Ciceley Race Team | 19th |
| 12.7.1998 | British GT Silverstone | 44 | Mantara LM500 | Jeff Wyatt | Forward GT Racing/Auriga Fibre Optics | NC |
| 12.7.1998 | 500 km Dijon | 70 | Mantara LM600 | Vann / Euser / Becker | Marcos Racing International | DNF |
| 12.7.1998 | 500 km Dijon | 71T | Mantara LM600 | | Marcos Racing International | unused |
| 12.7.1998 | British GT Silverstone | 77 | Mantara LM600 | Purvis / Sands | NCK Racing Ltd. | 13th |
| 19.7.1998 | 4 h Nürburgring | 30 | Mantara LM600 | Vann / Buurman | Marcos Racing International | 6th |
| 19.7.1998 | 500 km Hungaroring | 70 | Mantara LM600 | Euser / Becker | Marcos Racing International | 8th |
| 26.7.1998 | 4 h Spa | 30 | Mantara LM600 | Vann / Euser / Buurman | Marcos Racing International | DNF |
| 2.8.1998 | British GT Donington | 41 | Mantis | Russell Morgan | Ciceley Race Team | 16th |
| 2.8.1998 | British GT Donington | 44 | Mantara LM500 | Jeff Wyatt | Forward GT Racing | DNF |
| 2.8.1998 | British GT Donington | 76 | Mantara LM500 | Bob Sands | NCK Racing | DNA |
| 2.8.1998 | British GT Donington | 77 | Mantara LM600 | Erdos / Purvis | NCK Racing | DNF |
| 16.8.1998 | Belcar Assen | 22 | Mantara LM600 | Euser / Buurman / van Riet | | 1st |
| 23.8.1998 | British GT Silverstone | 44 | Mantara LM500 | Jeff Wyatt | Forward GT Racing | DNS |
| 23.8.1998 | 1000 km Suzuka | 70 | Mantara LM600 | Euser / Becker / Vann | Marcos Racing International | 11th |
| 23.8.1998 | British GT Silverstone | 77 | Mantara LM600 | Erdos / Purvis | NCK Racing | 6th |
| 6.9.1998 | 24 h Zolder | 21 | Mantara LM500 | Smolders / Buurman / Cauwberghs | Marcos Racing Team Belgium | raced |
| 6.9.1998 | 24 h Zolder | 22 | Mantis | Molenaers / Neyens / Vahsen | Marcos Racing Team Belgium | 11th |
| 6.9.1998 | 500 km Donington | 70 | Mantara LM600 | Euser / Becker / Vann | Marcos Racing International | DQ |
| 20.9.1998 | Belcar Zolder TSP | 22 | Mantis | Molenaers / Neyens | Marcos Racing Team Belgium | 13th |
| 20.9.1998 | FFSA GT Le Mans | 64 | Mantis Challenge | Howard Furr-Barton | Furr-Barton | - |
| 20.9.1998 | FFSA GT Le Mans | 69 | Mantis Challenge | Konig / Hayles | Hayles | 23rd/DNF |
| 20.9.1998 | FFSA GT Le Mans | 70 | Mantis Challenge | Cunningham / Breeze | Brookspeed Racing Ltd. | 15th/14th |
| 20.9.1998 | 500 km A1-Ring | 70 | Mantara LM600 | Becker / Euser / Vann | Marcos Racing International | DNF |
| 20.9.1998 | FFSA GT Le Mans | 73 | Mantis Challenge | Staveley / Holloway | | 21st/20th |
| 20.9.1998 | FFSA GT Le Mans | 77 | Mantis Challenge | Jackson / Liles | | 22nd/18th |
| 27.9.1998 | British GT Spa | 77 | Mantara LM600 | Erdos / Purvis | NCK Racing | 5th |
| 27.9.1998 | British GT Spa | 88 | Mantis | Ian Croft | Ian Croft | 13th |
| 4.10.1998 | British GT Silverstone | 44 | Mantara LM500 | Jeff Wyatt | Forward GT Racing | DNF |
| 4.10.1998 | British GT Silverstone | 57 | Mantis | Hann / Hall | Screwfix Direct | DNF |
| 4.10.1998 | British GT Silverstone | 77 | Mantara LM600 | Erdos / Purvis | NCK Racing | 6th |
| 10.10.1998 | Petit Le Mans | 59 | Mantara LM600 | Vann / Becker | Marcos Racing International | 27th |
| 11.10.1998 | Belcar Zolder BM | 22 | Mantis | Molenaers / Neyens | Marcos Racing Team Belgium | 19th |
| 18.10.1998 | FFSA GT Magny-Cours | 64 | Mantis Challenge | Howard Furr-Barton | Auto Vitesse | DNF/25th |
| 18.10.1998 | FFSA GT Magny-Cours | 69 | Mantis Challenge | Konig / Konig | Brookspeed Racing Ltd. | 32nd/28th |
| 18.10.1998 | 500 km Homestead | 70 | Mantara LM600 | Euser / Vann / Becker | Marcos Racing International | 10th |
| 18.10.1998 | FFSA GT Magny-Cours | 70 | Mantis Challenge | Cunningham / Hayles | Brookspeed Racing Ltd. | 26th/21st |
| 18.10.1998 | 500 km Homestead | 71 | Mantara LM600 | Schaafsma / Buurman | Marcos Racing International | 20th |
| 18.10.1998 | FFSA GT Magny-Cours | 84 | Mantis Challenge | Davies / Neuman | Davies | NC/27th |
| 25.10.1998 | 500 km Laguna Seca | 70 | Mantara LM600 | Euser / Vann / Becker | Marcos Racing International | DNF |
| 25.10.1998 | 2 h 30 min Laguna Seca | 71 | Mantara LM600 | Euser / Buurman | Marcos Racing International | 9th |
| 25.10.1998 | 500 km Laguna Seca | 71 | Mantara LM600 | Buurman / Schaafsma | Marcos Racing International | DNF |