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| 5/6/2023 | I-90 Speedway - Hartford, SD RPM Race Series Season Opener 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 4th | - | - | 15th (DNF) |
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| 5/20/2023 | I-90 Speedway - Hartford, SD Tri-State Late Models + RPM Race Series Dirt Late Models: Tri-State Late Models 305 Sprints - Winged, Dirt Super Late Models, B Modifieds, Street Stocks, USRA B-Mods, USRA Hobby Stocks, WISSOTA Late Model | Results | | Tanner Koster (USRA B-Mods) | 1st | - | - | 13th (DNF) |
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| 5/27/2023 | I-90 Speedway - Hartford, SD Northern Outlaw Sprints + RPM Race Series 410 Sprints - Winged, 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 1st | - | - | 3rd |
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| 6/3/2023 | I-90 Speedway - Hartford, SD RPM Race Series 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 7th | - | 8th | - |
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| 6/10/2023 | I-90 Speedway - Hartford, SD Midwest Sprint Touring Series + RPM Race Series 360 Sprints - Winged: Midwest Sprint Touring Series with Midwest Power Series 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 1st | - | - | 6th |
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| 6/16/2023 | Wagner Speedway - Wagner, SD Sport Mod Special Sprint Cars, B Modifieds, IMCA Northern SportMod, IMCA Stock Car, IMCA Hobby Stock, IMCA RaceSaver Sprint Car, IMCA Sport Compact, WISSOTA Midwest Mods | Results | | Tanner Koster (WISSOTA Midwest Mods) | 3rd | - | - | 12th |
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| 6/17/2023 | I-90 Speedway - Hartford, SD Hartford Night with RPM Race Series 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks, IMCA RaceSaver Sprint Car | Results | | Tanner Koster (USRA B-Mods) | 4th | - | - | 11th |
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| 6/20/2023 | Rapid Speedway - Rock Rapids, IA USRA Special + Sportsman DIRTcar Sportsmans, USRA B-Mods, USRA Hobby Stocks, USRA Stock Cars | Results | | Tanner Koster (USRA B-Mods) | 7th (DNF) | - | - | 16th |
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| 6/24/2023 | I-90 Speedway - Hartford, SD Kids' Night with RPM Race Series 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | - | - | - | - |
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| 7/1/2023 | I-90 Speedway - Hartford, SD Freedom Classic + Fireworks 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 5th | - | 3rd | 14th |
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| 7/8/2023 | I-90 Speedway - Hartford, SD RPM Race Series + Driver Meet and Greet 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 2nd | - | - | 15th (DNF) |
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| 7/15/2023 | I-90 Speedway - Hartford, SD Midwest Sprint Touring Series + RPM Race Series 360 Sprints - Winged: Midwest Sprint Touring Series 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 5th | - | - | 9th |
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| 7/22/2023 | I-90 Speedway - Hartford, SD Northern Outlaw Sprints + RPM Race Series (No LMSS) 410 Sprints - Winged, 305 Sprints - Winged, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 2nd | - | - | 5th |
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| 7/28/2023 | Rapid Speedway - Rock Rapids, IA Rapid Speedway Classes + Tri-State Late Models Dirt Late Models: Tri-State Late Models Dirt Super Late Models, DIRTcar Sportsmans, USRA B-Mods, USRA Hobby Stocks, USRA Stock Cars | Results | | Tanner Koster (USRA B-Mods) | 5th | - | - | 17th |
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| 7/29/2023 | I-90 Speedway - Hartford, SD RPM Race Series 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 5th | - | - | 10th |
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| 8/4/2023 | Rapid Speedway - Rock Rapids, IA Dave Mulder Memorial DIRTcar Sportsmans, USRA B-Mods, USRA Hobby Stocks, USRA Stock Cars | Results | | Tanner Koster (USRA B-Mods) | 6th | - | - | 13th |
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| 8/12/2023 | I-90 Speedway - Hartford, SD RPM Race Series + LMSS Pitstop Challenge 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 4th | - | - | 18th (DNF) |
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| 8/18/2023 | Rapid Speedway - Rock Rapids, IA Season Championship + Back to School Drive DIRTcar Late Models, DIRTcar Sportsmans, USRA B-Mods, USRA Hobby Stocks, USRA Stock Cars | Results | | Tanner Koster (USRA B-Mods) | 6th | - | - | 18th (DNF) |
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| 8/19/2023 | I-90 Speedway - Hartford, SD RPM Race Series + Powderpuff Special 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 4th | - | - | 1st |
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| 8/26/2023 | I-90 Speedway - Hartford, SD RPM Race Series 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 1st | - | - | 1st |
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| 9/2/2023 | I-90 Speedway - Hartford, SD Hobby Stock Pit Challenge / LMSS WingDing / USRA B-Mods Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 6th | - | - | 11th |
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| 9/9/2023 | I-90 Speedway - Hartford, SD RPM Race Series Season Championship 305 Sprints - Winged, Street Stocks, USRA B-Mods, USRA Hobby Stocks | Results | | Tanner Koster (USRA B-Mods) | 5th | - | - | 5th |
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| 9/14/2023 | Fairmont Raceway - Fairmont, MN 4TH ANNUAL BACONTOW SHOWDOWN USRA B-Mods, USRA Modifieds, USRA Hobby Stocks, USRA Stock Cars, USRA Tuners | Results | | Tanner Koster (USRA B-Mods) | 3rd | - | - | 11th |
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| 9/30/2023 | Murray County Speedway - Slayton, MN Hub City Rumble Factory Stocks, Hobby Stocks, Stock Cars, A Modifieds, B Modifieds, Sport Compact | Results | | Tanner Koster (B Modifieds) | 4th | - | - | 11th |
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| 10/6/2023 | Interstate Speedway (SD) - Jefferson, SD South Dakota Fall Nationals B Modifieds, IMCA Modified, IMCA Northern SportMod, IMCA Stock Car, IMCA Hobby Stock, IMCA Sport Compact | Results | | Tanner Koster (IMCA Northern SportMod) | 8th | - | - | - |
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| 10/7/2023 | Interstate Speedway (SD) - Jefferson, SD South Dakota Fall Nationals B Modifieds, IMCA Modified, IMCA Northern SportMod, IMCA Stock Car, IMCA Hobby Stock, IMCA Sport Compact | Results | | Tanner Koster (IMCA Northern SportMod) | 9th | - | 6th | - |
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| 10/21/2023 | Park Jefferson International Speedway - Jefferson, SD Charlie Clark Memorial $5022 to win! A Modifieds, B Modifieds, IMCA Modified, IMCA Northern SportMod, IMCA Stock Car, IMCA Hobby Stock, IMCA Sport Compact | Results | | Tanner Koster (IMCA Northern SportMod) | 8th | - | 8th | - |
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