C Sports Racer (CSR) now known as Prototype 1 (P1) is a class in the Sports Car Club of America. it consists of open top prototype style cars. The maximum displacement is 1615cc, in a 2 valve crossflow engine, with a minimum weight of 1300lbs w/driver. Two cycle or 4 valve/4 cycle motors between 850cc and 1300cc are permitted with a minimum weight of 1200lbs. Supercharging and turbocharging are permitted within limits, and with a maximum displacement of 765cc. Some CSRs are Formula Atlantic or Formula SCCA cars converted by adding bodywork to the chassis.[1]
| Year | Driver | Car | Engine | |
|---|---|---|---|---|
| C Modified | ||||
| 1954 |  Jim Kimberly | Ferrari 4.5 | ||
| 1955 | ||||
| 1956 | ||||
| 1957 | ||||
| 1958 | ||||
| 1959 | ||||
| 1960 | Richard Thompson | Chevrolet | ||
| 1961 | Peter Harrison | Chevrolet | ||
| 1962 | Harry Heuer | Chaparral I | Chevrolet | |
| 1963 | Harry Heuer | Chaparral I | Chevrolet | |
| 1964 | Ed Lowther | Huffaker Genie Mk. 10 | Ford | |
| 1965 | Joe Starkey | |||
| C Sports Racer | ||||
| 1966 | Ralph Salyer | McKee | Oldsmobile | |
| 1967 | Chevrolet | |||
| 1968 | Mario Whittington | Lotus 23 | Ford | |
| 1969 | Dan Carmichael | Lotus 23B | Ford | |
| 1970 | Dan Carmichael | Lotus 23B | Ford | |
| 1971 | Tom Evans | Gardner | Alfa Romeo | |
| 1972 | William Holbrook | Ford | ||
| 1973 | Eric Kerman | Arachnid | Ford | |
| 1974 | Samuel Gilliland | Arachnid 3 | Ford | |
| 1975 | Bobsy SR6 | Ford | ||
| 1976 | Fred Stevenson | Bobsy SR6 | Ford | |
| 1977 | Giuseppe Castellano | Lola T498 | Ford | |
| 1978 | Jeff Miller | |||
| 1979 | Tom Foster | Ford | ||
| 1980 | Fred Schilpin | Lola T496 | Ford | |
| 1981 | Tom Foster | Tiga SC81 | Ford | |
| 1982 | Terry McKenna | Argo JM4 Ocelot | Volkswagen | |
| 1983 | Charles Billington | Tracer TR2 | Ford | |
| 1984 | Tom Foster | Tracer TR2 | Ford | |
| 1985 | Tom Foster | Tracer TR2 | Volkswagen | |
| 1986 | Al Beasley | Bease Decker 2 | ||
| 1987 | Tom Foster | Tracer TR2 | Ford | |
| 1988 | Tom Foster | Tracer TR2 | Ford | |
| 1989 | Tom Foster | Tracer TR2 | Ford | |
| 1990 | Charles Billington | Tracer TR2 | Ford | |
| 1991 | Charles Billington | Tracer TR2 | Ford | |
| 1992 | Charles Billington | Tracer TR2 | Ford | |
| 1993 | Charles Billington | Tracer TR2 | Ford | |
| 1994 | Greg Harrington | Toyota | ||
| 1995 | Alexander Smith | Pratt & Miller RM2 | ||
| 1996 | Jeff Miller | Wynnfurst | ||
| 1997 | Charles Billington | Tracer TR2 | Ford | |
| 1998 | Ben Beasley | Beasley B2 | ||
| 1999 | Ben Beasley | Beasley B2 | ||
| 2000 | Alvin Beasley Jr. | Beasley B2 | ||
| 2001 | Ben Beasley | Beasley B7 | ||
| 2002 | Ben Beasley | Beasley B7 | ||
| 2003 | John Mirro | |||
| 2004 | Tony Loniewski | Swift Viking | Toyota | |
| 2005 | Arnstein Loyning | Swift Viking | Toyota | |
| 2006 | Peter Hans | Swift 014.a | Toyota | |
| 2007 | Peter Hans | Swift 014.a | Toyota | |
| 2008 | J.R. Osborne | Stohr WF1 | Suzuki | |
| 2009 | Matt Miller | Élan DP02 | Mazda | |
| 2010 | Steve Forrer | Ralt RT41 | Toyota | |
| 2011 | Steve Forrer | Ralt RT41 | Toyota | |
| 2012 | Steve Forrer | Ralt RT41 | Toyota | |
| 2013 | Lee Alexander | Stohr WF1 | Suzuki | |
| Prototype 1 | ||||
| 2014 | Chris Farrell | Stohr WF1 | Suzuki | |
| 2015 | Gianpaolo Ciancimino | Stohr WF1 | Suzuki | |
| 2016 | James Devenport | Norma M20 FC | Honda | |
| 2017 | Jonathan Eriksen | Stohr WF1 | Suzuki | |
| 2018 | James Devenport | Norma M20 FC | Honda | |
| 2019 | Todd Slusher | Elan DP02 | Mazda | |
| 2020 | Swift 014 | Toyota | ||
| 2021 | Lee Alexander | Stohr WF1 | Suzuki | |
| 2022 | Chip Romer | Mazda | ||
| 2023 | Todd Vanacore | Elan DP02 | Mazda | |